programming concepts - Page 554

c++ / c confusion

- by mrbuxley

Im trying to make a small app in c++ that saves midifiles with this library. http://musicnote.sourceforge.net/docs/html/index.html The sample code that is given on the homepage looks like this. #include "MusicNoteLib.h" void main() { MusicNoteLib::Player player; // Create the Player Object player.Play("C D E F G A B"); // Play the Music Notes on the default MIDI output port } This piece of code won't compile in Visual studio 2008, I get many errors like MusicNoteLib.h(22) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int I don't understand the error or where to start looking... There also was some dll files that can be used instead of this h file. #ifndef __MUSICNOTE_LIB_H__EBEE094C_FF6E_43a1_A6CE_D619564F9C6A__ #define __MUSICNOTE_LIB_H__EBEE094C_FF6E_43a1_A6CE_D619564F9C6A__ /** @file MusicNoteLib.h * \brief Main header file for accessing the MusicNote Library */ /// <Summary> /// This header file can be included directly in your project or through /// MusicNoteLib.h of the MusicNoteDll project. If included directly, this /// will be built directly as a satic library. If included through MusicNoteDll /// this will use dllImports through MUSICNOTELIB_API /// </Summary> #ifndef MUSICNOTELIB_API #define MUSICNOTELIB_API #endif // MUSICNOTELIB_API //#include "Player.h" namespace MusicNoteLib /// Music Programming Library { typedef void (__stdcall *LPFNTRACEPROC)(void* pUserData, const TCHAR* szTraceMsg); typedef void (__stdcall *LPFNERRORPROC)(void* pUserData, long lErrCode, const TCHAR* szErrorMsg, const TCHAR* szToken); extern "C" { MUSICNOTELIB_API typedef void MStringPlayer; MUSICNOTELIB_API void* GetCarnaticMusicNoteReader(); /// <Summary> /// Creates a MusicString Player object. /// </Summary> MUSICNOTELIB_API MStringPlayer* CreateMusicStringPlayer(); /// <Summary> /// Plays Music string notes on the default MIDI Output device with the default Timer Resolution. /// Use PlayMusicStringWithOpts() to use custom values. /// @param szMusicNotes the Music string to be played on the MIDI output device /// @return True if the notes were played successfully, False otherwise /// </Summary> MUSICNOTELIB_API bool PlayMusicString(const TCHAR* szMusicNotes); /// <Summary> /// Same as PlayMusicString() except that this method accepts Callbacks. /// The Trace and Error callbacks will be used during the Parse of the Music Notes. /// @param szMusicNotes the Music string to be played on the MIDI output device /// @param traceCallbackProc the Callback to used to report Trace messages /// @param errorCallbackProc the Callback to used to report Error messages /// @param pUserData any user supplied data that should be sent to the Callback /// @return True if the notes were played successfully, False otherwise /// </Summary> MUSICNOTELIB_API bool PlayMusicStringCB(const TCHAR* szMusicNotes, LPFNTRACEPROC traceCallbackProc, LPFNERRORPROC errorCallbackProc, void* pUserData); /// <Summary> /// Plays Music string notes on the given MIDI Output device using the given Timer Resolution. /// Use PlayMusicString() to use default values. /// @param szMusicNotes the Music notes to be played /// @param nMidiOutPortID the device ID of the MIDI output port to be used for the play /// @param nTimerResMS preferred MIDI timer resolution, in MilliSeconds /// @return True if Play was successful, False otherwise /// </Summary> MUSICNOTELIB_API bool PlayMusicStringWithOpts(const TCHAR* szMusicNotes, int nMidiOutPortID, unsigned int nTimerResMS); /// <Summary> /// Same as PlayMusicStringWithOpts() except that this method accepts Callbacks. /// The Trace and Error callbacks will be used during the Parse of the Music Notes. /// @param szMusicNotes the Music notes to be played /// @param nMidiOutPortID the device ID of the MIDI output port to be used for the play /// @param nTimerResMS preferred MIDI timer resolution, in MilliSeconds /// @param traceCallbackProc the Callback to used to report Trace messages /// @param errorCallbackProc the Callback to used to report Error messages /// @param pUserData any user supplied data that should be sent to the Callback /// @return True if Play was successful, False otherwise /// </Summary> MUSICNOTELIB_API bool PlayMusicStringWithOptsCB(const TCHAR* szMusicNotes, int nMidiOutPortID, unsigned int nTimerResMS, LPFNTRACEPROC traceCallbackProc, LPFNERRORPROC errorCallbackProc, void* pUserData); /// <Summary> /// Save the given MusicString content into a MIDI output file /// @param szMusicNotes Music Notes to be converted to MIDI output /// @param szOutputFilePath path of the MIDI output file /// @return True if the the content was saved successfully, False otherwise /// </Summary> MUSICNOTELIB_API bool SaveAsMidiFile(const TCHAR* szMusicNotes, const char* szOutputFilePath); //MUSICNOTELIB_API typedef void (*ParseErrorProc)(const MusicNoteLib::CParser*, MusicNoteLib::CParser::ErrorEventHandlerArgs* pEvArgs); //MUSICNOTELIB_API typedef void (*ParseTraceProc)(const MusicNoteLib::CParser*, MusicNoteLib::CParser::TraceEventHandlerArgs* pEvArgs); MUSICNOTELIB_API void Parse(const TCHAR* szNotes, LPFNTRACEPROC traceCallbackProc, void* pUserData); } // extern "C" } // namespace MusicNoteLib #endif // __MUSICNOTE_LIB_H__EBEE094C_FF6E_43a1_A6CE_D619564F9C6A__

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how to click on a button in python

- by Ciobanu Alexandru

Trying to build some bot for clicking "skip-ad" button on a page. So far, i manage to use Mechanize to load a web-driver browser and to connect to some page but Mechanize module do not support js directly so now i need something like Selenium if i understand correct. I am also a beginner in programming so please be specific. How can i use Selenium or if there is any other solution, please explain details. This is the inner html code for the button: <a id="skip-ad" class="btn btn-inverse" onclick="open_url('http://imgur.com/gallery/tDK9V68', 'go'); return false;" style="font-weight: bold; " target="_blank" href="http://imgur.com/gallery/tDK9V68"> … </a> And this is my source so far: #!/usr/bin/python # FILENAME: test.py import mechanize import os, time from random import choice, randrange prox_list = [] #list of common UAS to apply to each connection attempt to impersonate browsers user_agent_strings = [ 'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1468.0 Safari/537.36', 'Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.1) Gecko/2008071615 Fedora/3.0.1-1.fc9 Firefox/3.0.1', 'Opera/9.80 (Windows NT 6.0) Presto/2.12.388 Version/12.14', 'Opera/9.80 (Macintosh; Intel Mac OS X 10.6.8; U; fr) Presto/2.9.168 Version/11.52', 'Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:23.0) Gecko/20131011 Firefox/23.0', 'Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; Media Center PC 6.0; InfoPath.3; MS-RTC LM 8; Zune 4.7', 'Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0; .NET CLR 2.0.50727; SLCC2; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; Zune 4.0; Tablet PC 2.0; InfoPath.3; .NET4.0C; .NET4.0E)', 'Mozilla/5.0 (compatible; MSIE 10.6; Windows NT 6.1; Trident/5.0; InfoPath.2; SLCC1; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET CLR 2.0.50727) 3gpp-gba UNTRUSTED/1.0', 'Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.0; Trident/5.0; chromeframe/11.0.696.57)', 'Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; InfoPath.1; SV1; .NET CLR 3.8.36217; WOW64; en-US)', 'Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; GTB7.4; InfoPath.2; SV1; .NET CLR 3.3.69573; WOW64; en-US)' ] def load_proxy_list(target): #loads and parses the proxy list file = open(target, 'r') count = 0 for line in file: prox_list.append(line) count += 1 print "Loaded " + str(count) + " proxies!" load_proxy_list('proxies.txt') #for i in range(1,(len(prox_list) - 1)): # depreceated for overloading for i in range(1,30): br = mechanize.Browser() #pick a random UAS to add some extra cover to the bot br.addheaders = [('User-agent', choice(user_agent_strings))] print "----------------------------------------------------" #This is bad internet ethics br.set_handle_robots(False) #choose a proxy proxy = choice(prox_list) br.set_proxies({"http": proxy}) br.set_debug_http(True) try: print "Trying connection with: " + str(proxy) #currently using: BTC CoinURL - Grooveshark Broadcast br.open("http://cur.lv/4czwj") print "Opened successfully!" #act like a nice little drone and view the ads sleep_time_on_link = randrange(17.0,34.0) time.sleep(sleep_time_on_link) except mechanize.HTTPError, e: print "Oops Request threw " + str(e.code) #future versions will handle codes properly, 404 most likely means # the ad-linker has noticed bot-traffic and removed the link # or the used proxy is terrible. We will either geo-locate # proxies beforehand and pick good hosts, or ditch the link # which is worse case scenario, account is closed because of botting except mechanize.URLError, e: print "Oops! Request was refused, blacklisting proxy!" + str(e) prox_list.remove(proxy) del br #close browser entirely #wait between 5-30 seconds like a good little human sleep_time = randrange(5.0, 30.0) print "Waiting for %.1f seconds like a good bot." % (sleep_time) time.sleep(sleep_time)

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Runtime error on UVa Online Judge on Erdos Number

- by 2012 - End of the World

I am solving the Erdos number problem from the programming challenges in JAVA. The code runs perfectly in my machine. However on the online judge it results in a runtime error. Could anyone point out the mistake i made? http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=985 Here is the code import java.util.*; import java.io.*; class Main { private String inputLines[]; private String namesToBeFound[]; private String namesInEachBook[][]; private String searchItem; private boolean solnfound=false; private static final BufferedReader br =new BufferedReader(new InputStreamReader(System.in)); static String read() throws IOException { String line; while(true) { line=br.readLine(); if(line==null) break; //eof else if(line.length()==0) continue; //blank line else { line=line.trim().replaceAll("\\s+"," "); return line; } } return null; } public static void main(String args[]) throws IOException { Main ob=new Main(); int totalPapers,calcAuthors,totalScenarios; //First input number of scenarios totalScenarios=Integer.parseInt(read()); //Now start a loop for reading total number of scenarios for(int scenario=1;scenario<=totalScenarios;scenario++) { //Now read the line containing the number of papers and authors StringTokenizer line=new StringTokenizer(read()," "); totalPapers=Integer.parseInt(line.nextToken()); calcAuthors=Integer.parseInt(line.nextToken()); //Read a line containing author names along with book names ob.inputLines=new String[totalPapers]; for(int i=0;i<totalPapers;i++) ob.inputLines[i]=read(); //Read a line containing the names to be searched ob.namesToBeFound=new String[calcAuthors]; for(int i=0;i<calcAuthors;i++) ob.namesToBeFound[i]=read(); //Now generate the array ob.buildArray(); //Now search System.out.println("Scenario "+scenario); for(int i=0;i<calcAuthors;i++) { ob.searchItem=ob.namesToBeFound[i]; if(ob.searchItem.equals("Erdos, P.")) { System.out.println("Erdos, P. 0"); continue; } ob.search(ob.namesToBeFound[i],1,new ArrayList()); if(ob.solnfound==false) System.out.println(ob.searchItem+" infinity"); ob.solnfound=false; } } } private void buildArray() { String str; namesInEachBook=new String[inputLines.length][]; for(int i=0;i<inputLines.length;i++) { str=inputLines[i]; str=str.substring(0,str.indexOf(':')); str+=","; namesInEachBook[i]=new String[(countCommas(str)+1)>>1]; for(int j=0;j<namesInEachBook[i].length;j++) { str=str.trim(); namesInEachBook[i][j]=""; namesInEachBook[i][j]+=str.substring(0,str.indexOf(','))+","; str=str.substring(str.indexOf(',')+1); namesInEachBook[i][j]+=str.substring(0,str.indexOf(',')); str=str.substring(str.indexOf(',')+1); } } } private int countCommas(String s) { int num=0; for(int i=0;i<s.length();i++) if(s.charAt(i)==',') num++; return num; } private void search(String searchElem,int ernosDepth,ArrayList searchedElem) { ArrayList searchSpace=new ArrayList(); searchedElem.add(searchElem); for(int i=0;i<namesInEachBook.length;i++) for(int j=0;j<namesInEachBook[i].length;j++) { if(namesInEachBook[i][j].equals(searchElem)) //Add all authors name in this group { for(int k=0;k<namesInEachBook[i].length;k++) { if(namesInEachBook[i][k].equals("Erdos, P.")) //Found { solnfound=true; System.out.println(searchItem+" "+ernosDepth); return; } else if(searchedElem.contains(namesInEachBook[i][k]) || searchSpace.contains(namesInEachBook[i][k])) continue; searchSpace.add(namesInEachBook[i][k]); } break; } } Iterator i=searchSpace.iterator(); while(i.hasNext()) { String cSearchElem=(String)i.next(); search(cSearchElem,ernosDepth+1,searchedElem); } } }

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Login or Register (Ruby on rails)

- by DanielZ

Hello stackoverflow, I'm working on an Ruby on Rails application (2.3.x) and i want to make a form that lets the user login or register. I want to do this in the same form. I have a JS function that replaces the form elements like this: Login form: <% form_for @user do |f| %> <div id="form"> <%= f.label :email, "E-mail" %> <%= f.text_field :email %> <%= f.label :password, "Password" %> <%= f.password_field :password %> <%= link_to "I don't have an account, "#", :id => "changeForm"%> <%= f.submit "Login" %> </div> <% end %> The id "changeForm" triggers a JS function that changes the form elements. So if you press the url the html looks like this: <% form_for @user do |f| %> <div id="form"> <%= f.label :name, "Name" %> <%= f.text_field :name %> <%= f.label :email, "E-mail" %> <%= f.text_field :email %> <%= f.label :password, "Password" %> <%= f.password_field :password %> <%= f.label :password_confirmation, "Password confirmation" %> <%= f.password_field :password_confirmation %> <%= link_to "I do have an account, "#", :id => "changeForm"%> <%= f.submit "Register" %> </div> <% end %> I added the neccesary validations to my user model: class User < ActiveRecord::Base attr_reader :password validates_presence_of :name, :email, :password validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i validates_confirmation_of :password But what happens when you fill in the email / password you get the errors that the name is missing and that the password fields aren't confirmed. So i could do some nasty programming in my user model like this: #if password_conf or the name are present the user has tried to register... if params[:user][:password_confirmation].present? || params[:user][:name].present? #so we'll try to save the user if @user.save #if the user is saved authenticate the user current_session.user = User.authenticate(params[:user]) #if the user is logged in? if current_session.user.present? flash[:notice] = "succesvully logged redirect_to some_routes_path else #not logged in... flash[:notice] = "Not logged in" render :action => "new" end else #user not saved render :action => "new" end else #So if the params[:user][:password_confirmation] or [:user][:name] weren't present we geuss the user wants to login... current_session.user = User.authenticate(params[:user]) #are we logged_in? if current_session.user.present? flash[:notice] = "Succesvully logged in" redirect_to some_routes_path else #errors toevoegen @user.errors.add(:email, "The combination of email/password isn't valid") @user.errors.add(:password," ") render :action => "new" end end end Without validations this (imho dirty code and should not be in the controller) works. But i want to use the validates_presence_of methods and i don't want to slap the "conventions over configurations" in the face. So another thing i have tried is adding a hidden field to the form: #login form <%= f.hidden_field :login, :value => true %> # and ofcourse set it to false if we want to register. And then i wanted to use the method: before_validation before_validation_on_create do |user| if params[:user].login == true #throws an error i know... validates_presence_of :email, :password validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i else validates_presence_of :name, :email, :password validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i validates_confirmation_of :password end end But this doesn't work because i can't access the params. And login isn't a attribute for the user object. But i thought that in this way i could validate the email and password params if the user wants to login. And all the other attrs if the user want to register. So all i could think of doesn't work how i want it to work. So my main goal is this: 1 form for login/register with the use of the validation methods in the user model. So if we want to login but don't fill in any information = give validation errors. And if the user wants to login but the email/password combination doens't match give the "@user.errors.add(:email, "the combination wasn't found in the db...")". And the same goes for user register... Thanks in advance!

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Mistake in display and insert methods (double-ended queue)

- by MANAL

1) My problem when i make remove from right or left program will be remove true but when i call diplay method the content wrong like this I insert 12 43 65 23 and when make remove from left program will remove 12 but when call display method show like this 12 43 65 and when make remove from right program will remove 23 but when call display method show like this 12 43 Why ?????? ); and when i try to make insert after remove write this Can not insert right because the queue is full . first remove right and then u can insert right where is the problem ?? Please Help me please 2) My code FIRST CLASS class dqueue { private int fullsize; //number of all cells private int item_num; // number of busy cells only private int front,rear; public int j; private double [] dqarr; //========================================== public dqueue(int s) //constructor { fullsize = s; front = 0; rear = -1; item_num = 0; dqarr = new double[fullsize]; } //========================================== public void insert(double data) { if (rear == fullsize-1) rear = -1; rear++; dqarr[rear] = data; item_num++; } public double removeLeft() // take item from front of queue { double temp = dqarr[front++]; // get value and incr front if(front == fullsize) front = 0; item_num --; // one less item return temp; } public double removeRight() // take item from rear of queue { double temp = dqarr[rear--]; // get value and decr rear if(rear == -1) // rear = item_num -1; item_num --; // one less item return temp; } //========================================= public void display () //display items { for (int j=0;j<item_num;j++) // for every element System.out.print(dqarr[j] +" " ); // display it System.out.println(""); } //========================================= public int size() //number of items in queue { return item_num; } //========================================== public boolean isEmpty() // true if queue is empty { return (item_num ==0); } } SECOND CLASS import java.util.Scanner; class dqueuetest { public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.println(" ***** Welcome here***** "); System.out.println(" ***** Mind Of Programming Group***** "); System.out.println(" _____________________________________________ "); System.out.println("enter size of your dqueue"); int size = input.nextInt(); dqueue mydq = new dqueue(size); System.out.println(""); System.out.println("enter your itemes"); //===================================== for(int i = 0;i<=size-1;i++) { System.out.printf("item %d:",i+1); double item = input.nextDouble(); mydq.insert(item); System.out.println(""); } //===================================== int queue =size ; int c = 0 ; while (c != 6) { System.out.println(""); System.out.println("************************************************"); System.out.println(" MAIN MENUE"); System.out.println("1- INSERT RIGHT "); System.out.println("2- REMOVE LEFT"); System.out.println("3- REMOVE RIGHT"); System.out.println("4- DISPLAY"); System.out.println("5- SIZE"); System.out.println("6- EXIT"); System.out.println("************************************************"); System.out.println("choose your operation by number(1-6)"); c = input.nextInt(); switch (c) { case 1: if (queue == size) System.out.print("Can not insert right because the queue is full . first remove right and then u can insert right "); else { System.out.print("enter your item: "); double item = input.nextDouble(); mydq.insert(item);} break; case 2: System.out.println("REMOVE FROM REAR :"); if( !mydq.isEmpty() ) { double item = mydq.removeLeft(); System.out.print(item + "\t"); } // end while System.out.println(""); mydq.display(); break; case 3: System.out.println("REMOVE FROM FRONT :"); if( !mydq.isEmpty() ) { double item = mydq.removeRight(); System.out.print(item + "\t"); } // end while System.out.println(""); mydq.display(); break; case 4: System.out.println("The items in Queue are :"); mydq.display(); break; case 5: System.out.println("The Size of the Queue is :"+mydq.size()); break; case 6: System.out.println("Good Bye"); break; default: System.out.println("wrong chiose enter again"); } //end switch } //end while } // end main }//end class

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Does this language feature already exist?

- by Pindatjuh

I'm currently developing a new language for programming in a continuous environment (compare it to electrical engineering), and I've got some ideas on a certain language construction. Let me explain the feature by explanation and then by definition: x = a U b; Where x is a variable and a and b are other variables (or static values). This works like a union between a and b; no duplicates and no specific order. with(x) { // regular 'with' usage; using the global interpretation of "x" x = 5; // will replace the original definition of "x = a U b;" } with(x = a) { // this code block is executed when the "x" variable // has the "a" variable assigned. All references in // this code-block to "x" are references to "a". So saying: x = 5; // would only change the variable "a". If the variable "a" // later on changes, x still equals to 5, in this fashion: // 'x = a U b U 5;' // '[currentscope] = 5;' // thus, 'a = 5;' } with(x = b) { // same but with "b" } with(x != a) { // here the "x" variable refers to any variable // but "a"; thus saying x = 5; // is equal to the rewriting of // 'x = a U b U 5;' // 'b = 5;' (since it was the scope of this block) } with(x = (a U b)) { // guaranteed that "x" is 'a U b'; interacting with "x" // will interact with both "a" and "b". x = 5; // makes both "a" and "b" equal to 5; also the "x" variable // is updated to contain: // 'x = a U b U 5;' // '[currentscope] = 5;' // 'a U b = 5;' // and thus: 'a = 5; b = 5;'. } // etc. In the above, all code-blocks are executed, but the "scope" changes in each block how x is interpreted. In the first block, x is guaranteed to be a: thus interacting with x inside that block will interact on a. The second and the third code-block are only equal in this situation (because not a: then there only remains b). The last block guarantees that x is at least a or b. Further more; U is not the "bitwise or operator", but I've called it the "and/or"-operator. Its definition is: "U" = "and" U "or" (On my blog, http://cplang.wordpress.com/2009/12/19/binop-and-or/, there is more (mathematical) background information on this operator. It's loosely based on sets. Using different syntax, changed it in this question.) Update: more examples. print = "Hello world!" U "How are you?"; // this will print // both values, but the // order doesn't matter. // 'userkey' is a variable containing a key. with(userkey = "a") { print = userkey; // will only print "a". } with(userkey = ("shift" U "a")) { // pressed both "shift" and the "a" key. print = userkey; // will "print" shift and "a", even // if the user also pressed "ctrl": // the interpretation of "userkey" is changed, // such that it only contains the matched cases. } with((userkey = "shift") U (userkey = "a")) { // same as if-statement above this one, showing the distributivity. } x = 5 U 6 U 7; y = x + x; // will be: // y = (5 U 6 U 7) + (5 U 6 U 7) // = 10 U 11 U 12 U 13 U 14 somewantedkey = "ctrl" U "alt" U "space" with(userkey = somewantedkey) { // must match all elements of "somewantedkey" // (distributed the Boolean equals operated) // thus only executed when all the defined keys are pressed } with(somewantedkey = userkey) { // matches only one of the provided "somewantedkey" // thus when only "space" is pressed, this block is executed. } Update2: more examples and some more context. with(x = (a U b)) { // this } // can be written as with((x = a) U (x = b)) { // this: changing the variable like x = 5; // will be rewritten as: // a = 5 and b = 5 } Some background information: I'm building a language which is "time-independent", like Java is "platform-independant". Everything stated in the language is "as is", and is continuously actively executed. This means; the programmer does not know in which order (unless explicitly stated using constructions) elements are, nor when statements are executed. The language is completely separated from the "time"-concept, i.e. it's continuously executed: with(a < 5) { a++; } // this is a loop-structure; // how and when it's executed isn't known however. with(a) { // everytime the "a" variable changes, this code-block is executed. b = 4; with(b < 3) { // runs only three times. } with(b > 0) { b = b - 1; // runs four times } } Update 3: After pondering on the type of this language feature; it closely resemblances Netbeans Platform's Lookup, where each "with"-statement a synchronized agent is, working on it's specific "filter" of objects. Instead of type-based, this is variable-based (fundamentally quite the same; just a different way of identifiying objects). I greatly thank all of you for providing me with very insightful information and links/hints to great topics I can research. Thanks. I do not know if this construction already exists, so that's my question: does this language feature already exist?

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Sockets: Transport endpoint is not connected on send

- by TheoretiCAL

I'm trying to learn socket programming from http://beej.us/guide/bgnet/output/html/singlepage/bgnet.html and am attempting to build a SOCK_STREAM client/server. My client: #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <netdb.h> #define SERVERPORT "4951" // the port users will be connecting to int main(int argc, char *argv[]) { int sockfd; struct addrinfo hints, *servinfo, *p; int rv; int numbytes; if (argc != 3) { fprintf(stderr,"usage: talker hostname message\n"); exit(1); } memset(&hints, 0, sizeof hints); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; if ((rv = getaddrinfo(argv[1], SERVERPORT, &hints, &servinfo)) != 0) { fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv)); return 1; } // loop through all the results and make a socket for(p = servinfo; p != NULL; p = p->ai_next) { if ((sockfd = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1) { perror("talker: socket"); continue; if (connect(sockfd, p->ai_addr, p->ai_addrlen) == -1) { close(sockfd); perror("client: connect"); continue; } } break; } if (p == NULL) { fprintf(stderr, "talker: failed to bind socket\n"); return 2; } if ((numbytes = send(sockfd, argv[2], strlen(argv[2]), 0) == -1)) { perror("talker: send"); exit(1); } freeaddrinfo(servinfo); printf("talker: sent %d bytes to %s\n", numbytes, argv[1]); close(sockfd); return 0; } Server: #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <netdb.h> #define MYPORT "4951" // the port users will be connecting to #define MAXBUFLEN 100 static int backlog = 10; // get sockaddr, IPv4 or IPv6: void *get_in_addr(struct sockaddr *sa) { if (sa->sa_family == AF_INET) { return &(((struct sockaddr_in*)sa)->sin_addr); } return &(((struct sockaddr_in6*)sa)->sin6_addr); } int main(void) { int sockfd; struct addrinfo hints, *servinfo, *p; int rv; int numbytes; int new_fd; socklen_t addr_size; struct sockaddr_storage their_addr; char buf[MAXBUFLEN]; char s[INET6_ADDRSTRLEN]; memset(&hints, 0, sizeof hints); hints.ai_family = AF_UNSPEC; // set to AF_INET to force IPv4 hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_PASSIVE; // use my IP if ((rv = getaddrinfo(NULL, MYPORT, &hints, &servinfo)) != 0) { fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv)); return 1; } // loop through all the results and bind to the first we can for(p = servinfo; p != NULL; p = p->ai_next) { if ((sockfd = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1) { perror("listener: socket"); continue; } int yes=1; // lose the pesky "Address already in use" error message if (setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) { perror("setsockopt"); exit(1); } if (bind(sockfd, p->ai_addr, p->ai_addrlen) == -1) { close(sockfd); perror("listener: bind"); continue; } if (listen(sockfd,backlog) == -1){ close(sockfd); perror("listener:listen"); continue; } break; } if (p == NULL) { fprintf(stderr, "listener: failed to bind socket\n"); return 2; } freeaddrinfo(servinfo); printf("listener: waiting to recv..\n"); while(1){ addr_size = sizeof their_addr; if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &addr_size))==-1){ perror("accept"); exit(1); } if ((numbytes = recv(new_fd, buf, MAXBUFLEN-1 , 0) == -1)) { perror("recv"); exit(1); } printf("listener: got packet from %s\n", inet_ntop(their_addr.ss_family, get_in_addr((struct sockaddr *)&their_addr), s, sizeof s)); printf("listener: packet is %d bytes long\n", numbytes); buf[numbytes] = '\0'; printf("listener: packet contains \"%s\"\n", buf); close(sockfd); } return 0; } Upon executing the client, I get " send: Transport endpoint is not connected" and I'm not sure where I went wrong. Thanks.

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C++ Program performs better when piped

- by ET1 Nerd

I haven't done any programming in a decade. I wanted to get back into it, so I made this little pointless program as practice. The easiest way to describe what it does is with output of my --help codeblock: ./prng_bench --help ./prng_bench: usage: ./prng_bench $N $B [$T] This program will generate an N digit base(B) random number until all N digits are the same. Once a repeating N digit base(B) number is found, the following statistics are displayed: -Decimal value of all N digits. -Time & number of tries taken to randomly find. Optionally, this process is repeated T times. When running multiple repititions, averages for all N digit base(B) numbers are displayed at the end, as well as total time and total tries. My "problem" is that when the problem is "easy", say a 3 digit base 10 number, and I have it do a large number of passes the "total time" is less when piped to grep. ie: command ; command |grep took : ./prng_bench 3 10 999999 ; ./prng_bench 3 10 999999|grep took .... Pass# 999999: All 3 base(10) digits = 3 base(10). Time: 0.00005 secs. Tries: 23 It took 191.86701 secs & 99947208 tries to find 999999 repeating 3 digit base(10) numbers. An average of 0.00019 secs & 99 tries was needed to find each one. It took 159.32355 secs & 99947208 tries to find 999999 repeating 3 digit base(10) numbers. If I run the same command many times w/o grep time is always VERY close. I'm using srand(1234) for now, to test. The code between my calls to clock_gettime() for start and stop do not involve any stream manipulation, which would obviously affect time. I realize this is an exercise in futility, but I'd like to know why it behaves this way. Below is heart of the program. Here's a link to the full source on DB if anybody wants to compile and test. https://www.dropbox.com/s/6olqnnjf3unkm2m/prng_bench.cpp clock_gettime() requires -lrt. for (int pass_num=1; pass_num<=passes; pass_num++) { //Executes $passes # of times. clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &temp_time); //get time start_time = timetodouble(temp_time); //convert time to double, store as start_time for(i=1, tries=0; i!=0; tries++) { //loops until 'comparison for' fully completes. counts reps as 'tries'. <------------ for (i=0; i<Ndigits; i++) //Move forward through array. | results[i]=(rand()%base); //assign random num of base to element (digit). | /*for (i=0; i<Ndigits; i++) //---Debug Lines--------------- | std::cout<<" "<<results[i]; //---a LOT of output.---------- | std::cout << "\n"; //---Comment/decoment to disable/enable.*/ // | for (i=Ndigits-1; i>0 && results[i]==results[0]; i--); //Move through array, != element breaks & i!=0, new digits drawn. -| } //If all are equal i will be 0, nested for condition satisfied. -| clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &temp_time); //get time draw_time = (timetodouble(temp_time) - start_time); //convert time to dbl, subtract start_time, set draw_time to diff. total_time += draw_time; //add time for this pass to total. total_tries += tries; //add tries for this pass to total. /*Formated output for each pass: Pass# ---: All -- base(--) digits = -- base(10) Time: ----.---- secs. Tries: ----- (LINE) */ std::cout<<"Pass# "<<std::setw(width_pass)<<pass_num<<": All "<<Ndigits<<" base("<<base<<") digits = " <<std::setw(width_base)<<results[0]<<" base(10). Time: "<<std::setw(width_time)<<draw_time <<" secs. Tries: "<<tries<<"\n"; } if(passes==1) return 0; //No need for totals and averages of 1 pass. /* It took ----.---- secs & ------ tries to find --- repeating -- digit base(--) numbers. (LINE) An average of ---.---- secs & ---- tries was needed to find each one. (LINE)(LINE) */ std::cout<<"It took "<<total_time<<" secs & "<<total_tries<<" tries to find " <<passes<<" repeating "<<Ndigits<<" digit base("<<base<<") numbers.\n" <<"An average of "<<total_time/passes<<" secs & "<<total_tries/passes <<" tries was needed to find each one. \n\n"; return 0;

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How do I make my applet turn the user's input into an integer and compare it to the computer's random number?

- by Kitteran

I'm in beginning programming and I don't fully understand applets yet. However, (with some help from internet tutorials) I was able to create an applet that plays a game of guess with the user. The applet compiles fine, but when it runs, this error message appears: "Exception in thread "main" java.lang.NumberFormatException: For input string: "" at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48) at java.lang.Integer.parseInt(Integer.java:470) at java.lang.Integer.parseInt(Integer.java:499) at Guess.createUserInterface(Guess.java:101) at Guess.<init>(Guess.java:31) at Guess.main(Guess.java:129)" I've tried moving the "userguess = Integer.parseInt( t1.getText() );" on line 101 to multiple places, but I still get the same error. Can anyone tell me what I'm doing wrong? The Code: // Creates the game GUI. import javax.swing.*; import java.awt.*; import java.awt.event.*; public class Guess extends JFrame{ private JLabel userinputJLabel; private JLabel lowerboundsJLabel; private JLabel upperboundsJLabel; private JLabel computertalkJLabel; private JButton guessJButton; private JPanel guessJPanel; static int computernum; int userguess; static void declare() { computernum = (int) (100 * Math.random()) + 1; //random number picked (1-100) } // no-argument constructor public Guess() { createUserInterface(); } // create and position GUI components private void createUserInterface() { // get content pane and set its layout Container contentPane = getContentPane(); contentPane.setLayout( null ); contentPane.setBackground( Color.white ); // set up userinputJLabel userinputJLabel = new JLabel(); userinputJLabel.setText( "Enter Guess Here -->" ); userinputJLabel.setBounds( 0, 65, 120, 50 ); userinputJLabel.setHorizontalAlignment( JLabel.CENTER ); userinputJLabel.setBackground( Color.white ); userinputJLabel.setOpaque( true ); contentPane.add( userinputJLabel ); // set up lowerboundsJLabel lowerboundsJLabel = new JLabel(); lowerboundsJLabel.setText( "Lower Bounds Of Guess = 1" ); lowerboundsJLabel.setBounds( 0, 0, 170, 50 ); lowerboundsJLabel.setHorizontalAlignment( JLabel.CENTER ); lowerboundsJLabel.setBackground( Color.white ); lowerboundsJLabel.setOpaque( true ); contentPane.add( lowerboundsJLabel ); // set up upperboundsJLabel upperboundsJLabel = new JLabel(); upperboundsJLabel.setText( "Upper Bounds Of Guess = 100" ); upperboundsJLabel.setBounds( 250, 0, 170, 50 ); upperboundsJLabel.setHorizontalAlignment( JLabel.CENTER ); upperboundsJLabel.setBackground( Color.white ); upperboundsJLabel.setOpaque( true ); contentPane.add( upperboundsJLabel ); // set up computertalkJLabel computertalkJLabel = new JLabel(); computertalkJLabel.setText( "Computer Says:" ); computertalkJLabel.setBounds( 0, 130, 100, 50 ); //format (x, y, width, height) computertalkJLabel.setHorizontalAlignment( JLabel.CENTER ); computertalkJLabel.setBackground( Color.white ); computertalkJLabel.setOpaque( true ); contentPane.add( computertalkJLabel ); //Set up guess jbutton guessJButton = new JButton(); guessJButton.setText( "Enter" ); guessJButton.setBounds( 250, 78, 100, 30 ); contentPane.add( guessJButton ); guessJButton.addActionListener( new ActionListener() // anonymous inner class { // event handler called when Guess button is pressed public void actionPerformed( ActionEvent event ) { guessActionPerformed( event ); } } // end anonymous inner class ); // end call to addActionListener // set properties of application's window setTitle( "Guess Game" ); // set title bar text setSize( 500, 500 ); // set window size setVisible( true ); // display window //create text field TextField t1 = new TextField(); // Blank text field for user input t1.setBounds( 135, 78, 100, 30 ); contentPane.add( t1 ); userguess = Integer.parseInt( t1.getText() ); //create section for computertalk Label computertalkLabel = new Label(""); computertalkLabel.setBounds( 115, 130, 300, 50); contentPane.add( computertalkLabel ); } // Display computer reactions to user guess private void guessActionPerformed( ActionEvent event ) { if (userguess > computernum) //if statements (computer's reactions to user guess) computertalkJLabel.setText( "Computer Says: Too High" ); else if (userguess < computernum) computertalkJLabel.setText( "Computer Says: Too Low" ); else if (userguess == computernum) computertalkJLabel.setText( "Computer Says:You Win!" ); else computertalkJLabel.setText( "Computer Says: Error" ); } // end method oneJButtonActionPerformed // end method createUserInterface // main method public static void main( String args[] ) { Guess application = new Guess(); application.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE); } // end method main } // end class Phone

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Mistake in dispaly and insert method (double - ended queue)

- by MANAL

1) My problem when i make remove from right or left program will be remove true but when i call diplay method the content wrong like this I insert 12 43 65 23 and when make remove from left program will remove 12 but when call display method show like this 12 43 65 and when make remove from right program will remove 23 but when call display method show like this 12 43 Why ?????? ); and when i try to make insert after remove write this Can not insert right because the queue is full . first remove right and then u can insert right where is the problem ?? Please Help me please 2) My code FIRST CLASS class dqueue { private int fullsize; //number of all cells private int item_num; // number of busy cells only private int front,rear; public int j; private double [] dqarr; //========================================== public dqueue(int s) //constructor { fullsize = s; front = 0; rear = -1; item_num = 0; dqarr = new double[fullsize]; } //========================================== public void insert(double data) { if (rear == fullsize-1) rear = -1; rear++; dqarr[rear] = data; item_num++; } public double removeLeft() // take item from front of queue { double temp = dqarr[front++]; // get value and incr front if(front == fullsize) front = 0; item_num --; // one less item return temp; } public double removeRight() // take item from rear of queue { double temp = dqarr[rear--]; // get value and decr rear if(rear == -1) // rear = item_num -1; item_num --; // one less item return temp; } //========================================= public void display () //display items { for (int j=0;j //========================================= public int size() //number of items in queue { return item_num; } //========================================== public boolean isEmpty() // true if queue is empty { return (item_num ==0); } } SECOND CLASS import java.util.Scanner; class dqueuetest { public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.println(" Welcome here** "); System.out.println(" * Mind Of Programming Group*** "); System.out.println(" _________________________ "); System.out.println("enter size of your dqueue"); int size = input.nextInt(); dqueue mydq = new dqueue(size); System.out.println(""); System.out.println("enter your itemes"); //===================================== for(int i = 0;i<=size-1;i++) { System.out.printf("item %d:",i+1); double item = input.nextDouble(); mydq.insert(item); System.out.println(""); } //===================================== int queue =size ; int c = 0 ; while (c != 6) { System.out.println(""); System.out.println("**************************"); System.out.println(" MAIN MENUE"); System.out.println("1- INSERT RIGHT "); System.out.println("2- REMOVE LEFT"); System.out.println("3- REMOVE RIGHT"); System.out.println("4- DISPLAY"); System.out.println("5- SIZE"); System.out.println("6- EXIT"); System.out.println("**************************"); System.out.println("choose your operation by number(1-6)"); c = input.nextInt(); switch (c) { case 1: if (queue == size) System.out.print("Can not insert right because the queue is full . first remove right and then u can insert right "); else { System.out.print("enter your item: "); double item = input.nextDouble(); mydq.insert(item);} break; case 2: System.out.println("REMOVE FROM REAR :"); if( !mydq.isEmpty() ) { double item = mydq.removeLeft(); System.out.print(item + "\t"); } // end while System.out.println(""); mydq.display(); break; case 3: System.out.println("REMOVE FROM FRONT :"); if( !mydq.isEmpty() ) { double item = mydq.removeRight(); System.out.print(item + "\t"); } // end while System.out.println(""); mydq.display(); break; case 4: System.out.println("The items in Queue are :"); mydq.display(); break; case 5: System.out.println("The Size of the Queue is :"+mydq.size()); break; case 6: System.out.println("Good Bye"); break; default: System.out.println("wrong chiose enter again"); } //end switch } //end while } // end main }//end class

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Loop crashing program having to do with 2D arrays

- by user450062

I am creating an encoding program and when I instruct the program to create a 5X5 grid based on the alphabet while skipping over letters that match up to certain pre-defined variables(which are given values by user input during runtime). I have a loop that instructs the loop to keep running until the values that access the array are out of bounds, the loop seems to cause the problem. This code is standardized so there shouldn't be much trouble compiling it in another compiler. Also would it be better to seperate my program into functions? here is the code: #include<iostream> #include<fstream> #include<cstdlib> #include<string> #include<limits> using namespace std; int main(){ while (!cin.fail()) { char type[81]; char filename[20]; char key [5]; char f[2] = "q"; char g[2] = "q"; char h[2] = "q"; char i[2] = "q"; char j[2] = "q"; char k[2] = "q"; char l[2] = "q"; int a = 1; int b = 1; int c = 1; int d = 1; int e = 1; string cipherarraytemplate[5][5]= { {"a","b","c","d","e"}, {"f","g","h","i","j"}, {"k","l","m","n","o"}, {"p","r","s","t","u"}, {"v","w","x","y","z"} }; string cipherarray[5][5]= { {"a","b","c","d","e"}, {"f","g","h","i","j"}, {"k","l","m","n","o"}, {"p","r","s","t","u"}, {"v","w","x","y","z"} }; cout<<"Enter the name of a file you want to create.\n"; cin>>filename; ofstream outFile; outFile.open(filename); outFile<<fixed; outFile.precision(2); outFile.setf(ios_base::showpoint); cin.ignore(std::numeric_limits<int>::max(),'\n'); cout<<"enter your codeword(codeword can have no repeating letters)\n"; cin>>key; while (key[a] != '\0' ){ while(b < 6){ cipherarray[b][c] = key[a]; if ( f == "q" ) { cipherarray[b][c] = f; } if ( f != "q" && g == "q" ) { cipherarray[b][c] = g; } if ( g != "q" && h == "q" ) { cipherarray[b][c] = h; } if ( h != "q" && i == "q" ) { cipherarray[b][c] = i; } if ( i != "q" && j == "q" ) { cipherarray[b][c] = j; } if ( j != "q" && k == "q" ) { cipherarray[b][c] = k; } if ( k != "q" && l == "q" ) { cipherarray[b][c] = l; } a++; b++; } c++; b = 1; } while (c < 6 || b < 6){ if (cipherarraytemplate[d][e] == f || cipherarraytemplate[d][e] == g || cipherarraytemplate[d][e] == h || cipherarraytemplate[d][e] == i || cipherarraytemplate[d][e] == j || cipherarraytemplate[d][e] == k || cipherarraytemplate[d][e] == l){ d++; } else { cipherarray[b][c] = cipherarraytemplate[d][e]; d++; b++; } if (d == 6){ d = 1; e++; } if (b == 6){ c++; b = 1; } } cout<<"now enter some text."<<endl<<"To end this program press Crtl-Z\n"; while(!cin.fail()){ cin.getline(type,81); outFile<<type<<endl; } outFile.close(); } } I know there is going to be some mid-forties guy out there who is going to stumble on to this post, he's have been programming for 20-some years and he's going to look at my code and say: "what is this guy doing".

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Hosting the Razor Engine for Templating in Non-Web Applications

- by Rick Strahl

Microsoft’s new Razor HTML Rendering Engine that is currently shipping with ASP.NET MVC previews can be used outside of ASP.NET. Razor is an alternative view engine that can be used instead of the ASP.NET Page engine that currently works with ASP.NET WebForms and MVC. It provides a simpler and more readable markup syntax and is much more light weight in terms of functionality than the full blown WebForms Page engine, focusing only on features that are more along the lines of a pure view engine (or classic ASP!) with focus on expression and code rendering rather than a complex control/object model. Like the Page engine though, the parser understands .NET code syntax which can be embedded into templates, and behind the scenes the engine compiles markup and script code into an executing piece of .NET code in an assembly. Although it ships as part of the ASP.NET MVC and WebMatrix the Razor Engine itself is not directly dependent on ASP.NET or IIS or HTTP in any way. And although there are some markup and rendering features that are optimized for HTML based output generation, Razor is essentially a free standing template engine. And what’s really nice is that unlike the ASP.NET Runtime, Razor is fairly easy to host inside of your own non-Web applications to provide templating functionality. Templating in non-Web Applications? Yes please! So why might you host a template engine in your non-Web application? Template rendering is useful in many places and I have a number of applications that make heavy use of it. One of my applications – West Wind Html Help Builder - exclusively uses template based rendering to merge user supplied help text content into customizable and executable HTML markup templates that provide HTML output for CHM style HTML Help. This is an older product and it’s not actually using .NET at the moment – and this is one reason I’m looking at Razor for script hosting at the moment. For a few .NET applications though I’ve actually used the ASP.NET Runtime hosting to provide templating and mail merge style functionality and while that works reasonably well it’s a very heavy handed approach. It’s very resource intensive and has potential issues with versioning in various different versions of .NET. The generic implementation I created in the article above requires a lot of fix up to mimic an HTTP request in a non-HTTP environment and there are a lot of little things that have to happen to ensure that the ASP.NET runtime works properly most of it having nothing to do with the templating aspect but just satisfying ASP.NET’s requirements. The Razor Engine on the other hand is fairly light weight and completely decoupled from the ASP.NET runtime and the HTTP processing. Rather it’s a pure template engine whose sole purpose is to render text templates. Hosting this engine in your own applications can be accomplished with a reasonable amount of code (actually just a few lines with the tools I’m about to describe) and without having to fake HTTP requests. It’s also much lighter on resource usage and you can easily attach custom properties to your base template implementation to easily pass context from the parent application into templates all of which was rather complicated with ASP.NET runtime hosting. Installing the Razor Template Engine You can get Razor as part of the MVC 3 (RC and later) or Web Matrix. Both are available as downloadable components from the Web Platform Installer Version 3.0 (!important – V2 doesn’t show these components). If you already have that version of the WPI installed just fire it up. You can get the latest version of the Web Platform Installer from here: http://www.microsoft.com/web/gallery/install.aspx Once the platform Installer 3.0 is installed install either MVC 3 or ASP.NET Web Pages. Once installed you’ll find a System.Web.Razor assembly in C:\Program Files\Microsoft ASP.NET\ASP.NET Web Pages\v1.0\Assemblies\System.Web.Razor.dll which you can add as a reference to your project. Creating a Wrapper The basic Razor Hosting API is pretty simple and you can host Razor with a (large-ish) handful of lines of code. I’ll show the basics of it later in this article. However, if you want to customize the rendering and handle assembly and namespace includes for the markup as well as deal with text and file inputs as well as forcing Razor to run in a separate AppDomain so you can unload the code-generated assemblies and deal with assembly caching for re-used templates little more work is required to create something that is more easily reusable. For this reason I created a Razor Hosting wrapper project that combines a bunch of this functionality into an easy to use hosting class, a hosting factory that can load the engine in a separate AppDomain and a couple of hosting containers that provided folder based and string based caching for templates for an easily embeddable and reusable engine with easy to use syntax. If you just want the code and play with the samples and source go grab the latest code from the Subversion Repository at: http://www.west-wind.com:8080/svn/articles/trunk/RazorHosting/ or a snapshot from: http://www.west-wind.com/files/tools/RazorHosting.zip Getting Started Before I get into how hosting with Razor works, let’s take a look at how you can get up and running quickly with the wrapper classes provided. It only takes a few lines of code. The easiest way to use these Razor Hosting Wrappers is to use one of the two HostContainers provided. One is for hosting Razor scripts in a directory and rendering them as relative paths from these script files on disk. The other HostContainer serves razor scripts from string templates… Let’s start with a very simple template that displays some simple expressions, some code blocks and demonstrates rendering some data from contextual data that you pass to the template in the form of a ‘context’. Here’s a simple Razor template: @using System.Reflection Hello @Context.FirstName! Your entry was entered on: @Context.Entered @{ // Code block: Update the host Windows Form passed in through the context Context.WinForm.Text = "Hello World from Razor at " + DateTime.Now.ToString(); } AppDomain Id: @AppDomain.CurrentDomain.FriendlyName Assembly: @Assembly.GetExecutingAssembly().FullName Code based output: @{ // Write output with Response object from code string output = string.Empty; for (int i = 0; i < 10; i++) { output += i.ToString() + " "; } Response.Write(output); } Pretty easy to see what’s going on here. The only unusual thing in this code is the Context object which is an arbitrary object I’m passing from the host to the template by way of the template base class. I’m also displaying the current AppDomain and the executing Assembly name so you can see how compiling and running a template actually loads up new assemblies. Also note that as part of my context I’m passing a reference to the current Windows Form down to the template and changing the title from within the script. It’s a silly example, but it demonstrates two-way communication between host and template and back which can be very powerful. The easiest way to quickly render this template is to use the RazorEngine<TTemplateBase> class. The generic parameter specifies a template base class type that is used by Razor internally to generate the class it generates from a template. The default implementation provided in my RazorHosting wrapper is RazorTemplateBase. Here’s a simple one that renders from a string and outputs a string: var engine = new RazorEngine<RazorTemplateBase>(); // we can pass any object as context - here create a custom context var context = new CustomContext() { WinForm = this, FirstName = "Rick", Entered = DateTime.Now.AddDays(-10) }; string output = engine.RenderTemplate(this.txtSource.Text new string[] { "System.Windows.Forms.dll" }, context); if (output == null) this.txtResult.Text = "*** ERROR:\r\n" + engine.ErrorMessage; else this.txtResult.Text = output; Simple enough. This code renders a template from a string input and returns a result back as a string. It creates a custom context and passes that to the template which can then access the Context’s properties. Note that anything passed as ‘context’ must be serializable (or MarshalByRefObject) – otherwise you get an exception when passing the reference over AppDomain boundaries (discussed later). Passing a context is optional, but is a key feature in being able to share data between the host application and the template. Note that we use the Context object to access FirstName, Entered and even the host Windows Form object which is used in the template to change the Window caption from within the script! In the code above all the work happens in the RenderTemplate method which provide a variety of overloads to read and write to and from strings, files and TextReaders/Writers. Here’s another example that renders from a file input using a TextReader: using (reader = new StreamReader("templates\\simple.csHtml", true)) { result = host.RenderTemplate(reader, new string[] { "System.Windows.Forms.dll" }, this.CustomContext); } RenderTemplate() is fairly high level and it handles loading of the runtime, compiling into an assembly and rendering of the template. If you want more control you can use the lower level methods to control each step of the way which is important for the HostContainers I’ll discuss later. Basically for those scenarios you want to separate out loading of the engine, compiling into an assembly and then rendering the template from the assembly. Why? So we can keep assemblies cached. In the code above a new assembly is created for each template rendered which is inefficient and uses up resources. Depending on the size of your templates and how often you fire them you can chew through memory very quickly. This slighter lower level approach is only a couple of extra steps: // we can pass any object as context - here create a custom context var context = new CustomContext() { WinForm = this, FirstName = "Rick", Entered = DateTime.Now.AddDays(-10) }; var engine = new RazorEngine<RazorTemplateBase>(); string assId = null; using (StringReader reader = new StringReader(this.txtSource.Text)) { assId = engine.ParseAndCompileTemplate(new string[] { "System.Windows.Forms.dll" }, reader); } string output = engine.RenderTemplateFromAssembly(assId, context); if (output == null) this.txtResult.Text = "*** ERROR:\r\n" + engine.ErrorMessage; else this.txtResult.Text = output; The difference here is that you can capture the assembly – or rather an Id to it – and potentially hold on to it to render again later assuming the template hasn’t changed. The HostContainers take advantage of this feature to cache the assemblies based on certain criteria like a filename and file time step or a string hash that if not change indicate that an assembly can be reused. Note that ParseAndCompileTemplate returns an assembly Id rather than the assembly itself. This is done so that that the assembly always stays in the host’s AppDomain and is not passed across AppDomain boundaries which would cause load failures. We’ll talk more about this in a minute but for now just realize that assemblies references are stored in a list and are accessible by this ID to allow locating and re-executing of the assembly based on that id. Reuse of the assembly avoids recompilation overhead and creation of yet another assembly that loads into the current AppDomain. You can play around with several different versions of the above code in the main sample form: Using Hosting Containers for more Control and Caching The above examples simply render templates into assemblies each and every time they are executed. While this works and is even reasonably fast, it’s not terribly efficient. If you render templates more than once it would be nice if you could cache the generated assemblies for example to avoid re-compiling and creating of a new assembly each time. Additionally it would be nice to load template assemblies into a separate AppDomain optionally to be able to be able to unload assembli es and also to protect your host application from scripting attacks with malicious template code. Hosting containers provide also provide a wrapper around the RazorEngine<T> instance, a factory (which allows creation in separate AppDomains) and an easy way to start and stop the container ‘runtime’. The Razor Hosting samples provide two hosting containers: RazorFolderHostContainer and StringHostContainer. The folder host provides a simple runtime environment for a folder structure similar in the way that the ASP.NET runtime handles a virtual directory as it’s ‘application' root. Templates are loaded from disk in relative paths and the resulting assemblies are cached unless the template on disk is changed. The string host also caches templates based on string hashes – if the same string is passed a second time a cached version of the assembly is used. Here’s how HostContainers work. I’ll use the FolderHostContainer because it’s likely the most common way you’d use templates – from disk based templates that can be easily edited and maintained on disk. The first step is to create an instance of it and keep it around somewhere (in the example it’s attached as a property to the Form): RazorFolderHostContainer Host = new RazorFolderHostContainer(); public RazorFolderHostForm() { InitializeComponent(); // The base path for templates - templates are rendered with relative paths // based on this path. Host.TemplatePath = Path.Combine(Environment.CurrentDirectory, TemplateBaseFolder); // Add any assemblies you want reference in your templates Host.ReferencedAssemblies.Add("System.Windows.Forms.dll"); // Start up the host container Host.Start(); } Next anytime you want to render a template you can use simple code like this: private void RenderTemplate(string fileName) { // Pass the template path via the Context var relativePath = Utilities.GetRelativePath(fileName, Host.TemplatePath); if (!Host.RenderTemplate(relativePath, this.Context, Host.RenderingOutputFile)) { MessageBox.Show("Error: " + Host.ErrorMessage); return; } this.webBrowser1.Navigate("file://" + Host.RenderingOutputFile); } You can also render the output to a string instead of to a file: string result = Host.RenderTemplateToString(relativePath,context); Finally if you want to release the engine and shut down the hosting AppDomain you can simply do: Host.Stop(); Stopping the AppDomain and restarting it (ie. calling Stop(); followed by Start()) is also a nice way to release all resources in the AppDomain. The FolderBased domain also supports partial Rendering based on root path based relative paths with the same caching characteristics as the main templates. From within a template you can call out to a partial like this: @RenderPartial(@"partials\PartialRendering.cshtml", Context) where partials\PartialRendering.cshtml is a relative to the template root folder. The folder host example lets you load up templates from disk and display the result in a Web Browser control which demonstrates using Razor HTML output from templates that contain HTML syntax which happens to me my target scenario for Html Help Builder. The Razor Engine Wrapper Project The project I created to wrap Razor hosting has a fair bit of code and a number of classes associated with it. Most of the components are internally used and as you can see using the final RazorEngine<T> and HostContainer classes is pretty easy. The classes are extensible and I suspect developers will want to build more customized host containers for their applications. Host containers are the key to wrapping up all functionality – Engine, BaseTemplate, AppDomain Hosting, Caching etc in a logical piece that is ready to be plugged into an application. When looking at the code there are a couple of core features provided: Core Razor Engine Hosting This is the core Razor hosting which provides the basics of loading a template, compiling it into an assembly and executing it. This is fairly straightforward, but without a host container that can cache assemblies based on some criteria templates are recompiled and re-created each time which is inefficient (although pretty fast). The base engine wrapper implementation also supports hosting the Razor runtime in a separate AppDomain for security and the ability to unload it on demand. Host Containers The engine hosting itself doesn’t provide any sort of ‘runtime’ service like picking up files from disk, caching assemblies and so forth. So my implementation provides two HostContainers: RazorFolderHostContainer and RazorStringHostContainer. The FolderHost works off a base directory and loads templates based on relative paths (sort of like the ASP.NET runtime does off a virtual). The HostContainers also deal with caching of template assemblies – for the folder host the file date is tracked and checked for updates and unless the template is changed a cached assembly is reused. The StringHostContainer similiarily checks string hashes to figure out whether a particular string template was previously compiled and executed. The HostContainers also act as a simple startup environment and a single reference to easily store and reuse in an application. TemplateBase Classes The template base classes are the base classes that from which the Razor engine generates .NET code. A template is parsed into a class with an Execute() method and the class is based on this template type you can specify. RazorEngine<TBaseTemplate> can receive this type and the HostContainers default to specific templates in their base implementations. Template classes are customizable to allow you to create templates that provide application specific features and interaction from the template to your host application. How does the RazorEngine wrapper work? You can browse the source code in the links above or in the repository or download the source, but I’ll highlight some key features here. Here’s part of the RazorEngine implementation that can be used to host the runtime and that demonstrates the key code required to host the Razor runtime. The RazorEngine class is implemented as a generic class to reflect the Template base class type: public class RazorEngine<TBaseTemplateType> : MarshalByRefObject where TBaseTemplateType : RazorTemplateBase The generic type is used to internally provide easier access to the template type and assignments on it as part of the template processing. The class also inherits MarshalByRefObject to allow execution over AppDomain boundaries – something that all the classes discussed here need to do since there is much interaction between the host and the template. The first two key methods deal with creating a template assembly: /// <summary> /// Creates an instance of the RazorHost with various options applied. /// Applies basic namespace imports and the name of the class to generate /// </summary> /// <param name="generatedNamespace"></param> /// <param name="generatedClass"></param> /// <returns></returns> protected RazorTemplateEngine CreateHost(string generatedNamespace, string generatedClass) { Type baseClassType = typeof(TBaseTemplateType); RazorEngineHost host = new RazorEngineHost(new CSharpRazorCodeLanguage()); host.DefaultBaseClass = baseClassType.FullName; host.DefaultClassName = generatedClass; host.DefaultNamespace = generatedNamespace; host.NamespaceImports.Add("System"); host.NamespaceImports.Add("System.Text"); host.NamespaceImports.Add("System.Collections.Generic"); host.NamespaceImports.Add("System.Linq"); host.NamespaceImports.Add("System.IO"); return new RazorTemplateEngine(host); } /// <summary> /// Parses and compiles a markup template into an assembly and returns /// an assembly name. The name is an ID that can be passed to /// ExecuteTemplateByAssembly which picks up a cached instance of the /// loaded assembly. /// /// </summary> /// <param name="namespaceOfGeneratedClass">The namespace of the class to generate from the template</param> /// <param name="generatedClassName">The name of the class to generate from the template</param> /// <param name="ReferencedAssemblies">Any referenced assemblies by dll name only. Assemblies must be in execution path of host or in GAC.</param> /// <param name="templateSourceReader">Textreader that loads the template</param> /// <remarks> /// The actual assembly isn't returned here to allow for cross-AppDomain /// operation. If the assembly was returned it would fail for cross-AppDomain /// calls. /// </remarks> /// <returns>An assembly Id. The Assembly is cached in memory and can be used with RenderFromAssembly.</returns> public string ParseAndCompileTemplate( string namespaceOfGeneratedClass, string generatedClassName, string[] ReferencedAssemblies, TextReader templateSourceReader) { RazorTemplateEngine engine = CreateHost(namespaceOfGeneratedClass, generatedClassName); // Generate the template class as CodeDom GeneratorResults razorResults = engine.GenerateCode(templateSourceReader); // Create code from the codeDom and compile CSharpCodeProvider codeProvider = new CSharpCodeProvider(); CodeGeneratorOptions options = new CodeGeneratorOptions(); // Capture Code Generated as a string for error info // and debugging LastGeneratedCode = null; using (StringWriter writer = new StringWriter()) { codeProvider.GenerateCodeFromCompileUnit(razorResults.GeneratedCode, writer, options); LastGeneratedCode = writer.ToString(); } CompilerParameters compilerParameters = new CompilerParameters(ReferencedAssemblies); // Standard Assembly References compilerParameters.ReferencedAssemblies.Add("System.dll"); compilerParameters.ReferencedAssemblies.Add("System.Core.dll"); compilerParameters.ReferencedAssemblies.Add("Microsoft.CSharp.dll"); // dynamic support! // Also add the current assembly so RazorTemplateBase is available compilerParameters.ReferencedAssemblies.Add(Assembly.GetExecutingAssembly().CodeBase.Substring(8)); compilerParameters.GenerateInMemory = Configuration.CompileToMemory; if (!Configuration.CompileToMemory) compilerParameters.OutputAssembly = Path.Combine(Configuration.TempAssemblyPath, "_" + Guid.NewGuid().ToString("n") + ".dll"); CompilerResults compilerResults = codeProvider.CompileAssemblyFromDom(compilerParameters, razorResults.GeneratedCode); if (compilerResults.Errors.Count > 0) { var compileErrors = new StringBuilder(); foreach (System.CodeDom.Compiler.CompilerError compileError in compilerResults.Errors) compileErrors.Append(String.Format(Resources.LineX0TColX1TErrorX2RN, compileError.Line, compileError.Column, compileError.ErrorText)); this.SetError(compileErrors.ToString() + "\r\n" + LastGeneratedCode); return null; } AssemblyCache.Add(compilerResults.CompiledAssembly.FullName, compilerResults.CompiledAssembly); return compilerResults.CompiledAssembly.FullName; } Think of the internal CreateHost() method as setting up the assembly generated from each template. Each template compiles into a separate assembly. It sets up namespaces, and assembly references, the base class used and the name and namespace for the generated class. ParseAndCompileTemplate() then calls the CreateHost() method to receive the template engine generator which effectively generates a CodeDom from the template – the template is turned into .NET code. The code generated from our earlier example looks something like this: //------------------------------------------------------------------------------ // <auto-generated> // This code was generated by a tool. // Runtime Version:4.0.30319.1 // // Changes to this file may cause incorrect behavior and will be lost if // the code is regenerated. // </auto-generated> //------------------------------------------------------------------------------ namespace RazorTest { using System; using System.Text; using System.Collections.Generic; using System.Linq; using System.IO; using System.Reflection; public class RazorTemplate : RazorHosting.RazorTemplateBase { #line hidden public RazorTemplate() { } public override void Execute() { WriteLiteral("Hello "); Write(Context.FirstName); WriteLiteral("! Your entry was entered on: "); Write(Context.Entered); WriteLiteral("\r\n\r\n"); // Code block: Update the host Windows Form passed in through the context Context.WinForm.Text = "Hello World from Razor at " + DateTime.Now.ToString(); WriteLiteral("\r\nAppDomain Id:\r\n "); Write(AppDomain.CurrentDomain.FriendlyName); WriteLiteral("\r\n \r\nAssembly:\r\n "); Write(Assembly.GetExecutingAssembly().FullName); WriteLiteral("\r\n\r\nCode based output: \r\n"); // Write output with Response object from code string output = string.Empty; for (int i = 0; i < 10; i++) { output += i.ToString() + " "; } } } } Basically the template’s body is turned into code in an Execute method that is called. Internally the template’s Write method is fired to actually generate the output. Note that the class inherits from RazorTemplateBase which is the generic parameter I used to specify the base class when creating an instance in my RazorEngine host: var engine = new RazorEngine<RazorTemplateBase>(); This template class must be provided and it must implement an Execute() and Write() method. Beyond that you can create any class you chose and attach your own properties. My RazorTemplateBase class implementation is very simple: public class RazorTemplateBase : MarshalByRefObject, IDisposable { /// <summary> /// You can pass in a generic context object /// to use in your template code /// </summary> public dynamic Context { get; set; } /// <summary> /// Class that generates output. Currently ultra simple /// with only Response.Write() implementation. /// </summary> public RazorResponse Response { get; set; } public object HostContainer {get; set; } public object Engine { get; set; } public RazorTemplateBase() { Response = new RazorResponse(); } public virtual void Write(object value) { Response.Write(value); } public virtual void WriteLiteral(object value) { Response.Write(value); } /// <summary> /// Razor Parser implements this method /// </summary> public virtual void Execute() {} public virtual void Dispose() { if (Response != null) { Response.Dispose(); Response = null; } } } Razor fills in the Execute method when it generates its subclass and uses the Write() method to output content. As you can see I use a RazorResponse() class here to generate output. This isn’t necessary really, as you could use a StringBuilder or StringWriter() directly, but I prefer using Response object so I can extend the Response behavior as needed. The RazorResponse class is also very simple and merely acts as a wrapper around a TextWriter: public class RazorResponse : IDisposable { /// <summary> /// Internal text writer - default to StringWriter() /// </summary> public TextWriter Writer = new StringWriter(); public virtual void Write(object value) { Writer.Write(value); } public virtual void WriteLine(object value) { Write(value); Write("\r\n"); } public virtual void WriteFormat(string format, params object[] args) { Write(string.Format(format, args)); } public override string ToString() { return Writer.ToString(); } public virtual void Dispose() { Writer.Close(); } public virtual void SetTextWriter(TextWriter writer) { // Close original writer if (Writer != null) Writer.Close(); Writer = writer; } } The Rendering Methods of RazorEngine At this point I’ve talked about the assembly generation logic and the template implementation itself. What’s left is that once you’ve generated the assembly is to execute it. The code to do this is handled in the various RenderXXX methods of the RazorEngine class. Let’s look at the lowest level one of these which is RenderTemplateFromAssembly() and a couple of internal support methods that handle instantiating and invoking of the generated template method: public string RenderTemplateFromAssembly( string assemblyId, string generatedNamespace, string generatedClass, object context, TextWriter outputWriter) { this.SetError(); Assembly generatedAssembly = AssemblyCache[assemblyId]; if (generatedAssembly == null) { this.SetError(Resources.PreviouslyCompiledAssemblyNotFound); return null; } string className = generatedNamespace + "." + generatedClass; Type type; try { type = generatedAssembly.GetType(className); } catch (Exception ex) { this.SetError(Resources.UnableToCreateType + className + ": " + ex.Message); return null; } // Start with empty non-error response (if we use a writer) string result = string.Empty; using(TBaseTemplateType instance = InstantiateTemplateClass(type)) { if (instance == null) return null; if (outputWriter != null) instance.Response.SetTextWriter(outputWriter); if (!InvokeTemplateInstance(instance, context)) return null; // Capture string output if implemented and return // otherwise null is returned if (outputWriter == null) result = instance.Response.ToString(); } return result; } protected virtual TBaseTemplateType InstantiateTemplateClass(Type type) { TBaseTemplateType instance = Activator.CreateInstance(type) as TBaseTemplateType; if (instance == null) { SetError(Resources.CouldnTActivateTypeInstance + type.FullName); return null; } instance.Engine = this; // If a HostContainer was set pass that to the template too instance.HostContainer = this.HostContainer; return instance; } /// <summary> /// Internally executes an instance of the template, /// captures errors on execution and returns true or false /// </summary> /// <param name="instance">An instance of the generated template</param> /// <returns>true or false - check ErrorMessage for errors</returns> protected virtual bool InvokeTemplateInstance(TBaseTemplateType instance, object context) { try { instance.Context = context; instance.Execute(); } catch (Exception ex) { this.SetError(Resources.TemplateExecutionError + ex.Message); return false; } finally { // Must make sure Response is closed instance.Response.Dispose(); } return true; } The RenderTemplateFromAssembly method basically requires the namespace and class to instantate and creates an instance of the class using InstantiateTemplateClass(). It then invokes the method with InvokeTemplateInstance(). These two methods are broken out because they are re-used by various other rendering methods and also to allow subclassing and providing additional configuration tasks to set properties and pass values to templates at execution time. In the default mode instantiation sets the Engine and HostContainer (discussed later) so the template can call back into the template engine, and the context is set when the template method is invoked. The various RenderXXX methods use similar code although they create the assemblies first. If you’re after potentially cashing assemblies the method is the one to call and that’s exactly what the two HostContainer classes do. More on that in a minute, but before we get into HostContainers let’s talk about AppDomain hosting and the like. Running Templates in their own AppDomain With the RazorEngine class above, when a template is parsed into an assembly and executed the assembly is created (in memory or on disk – you can configure that) and cached in the current AppDomain. In .NET once an assembly has been loaded it can never be unloaded so if you’re loading lots of templates and at some time you want to release them there’s no way to do so. If however you load the assemblies in a separate AppDomain that new AppDomain can be unloaded and the assemblies loaded in it with it. In order to host the templates in a separate AppDomain the easiest thing to do is to run the entire RazorEngine in a separate AppDomain. Then all interaction occurs in the other AppDomain and no further changes have to be made. To facilitate this there is a RazorEngineFactory which has methods that can instantiate the RazorHost in a separate AppDomain as well as in the local AppDomain. The host creates the remote instance and then hangs on to it to keep it alive as well as providing methods to shut down the AppDomain and reload the engine. Sounds complicated but cross-AppDomain invocation is actually fairly easy to implement. Here’s some of the relevant code from the RazorEngineFactory class. Like the RazorEngine this class is generic and requires a template base type in the generic class name: public class RazorEngineFactory<TBaseTemplateType> where TBaseTemplateType : RazorTemplateBase Here are the key methods of interest: /// <summary> /// Creates an instance of the RazorHost in a new AppDomain. This /// version creates a static singleton that that is cached and you /// can call UnloadRazorHostInAppDomain to unload it. /// </summary> /// <returns></returns> public static RazorEngine<TBaseTemplateType> CreateRazorHostInAppDomain() { if (Current == null) Current = new RazorEngineFactory<TBaseTemplateType>(); return Current.GetRazorHostInAppDomain(); } public static void UnloadRazorHostInAppDomain() { if (Current != null) Current.UnloadHost(); Current = null; } /// <summary> /// Instance method that creates a RazorHost in a new AppDomain. /// This method requires that you keep the Factory around in /// order to keep the AppDomain alive and be able to unload it. /// </summary> /// <returns></returns> public RazorEngine<TBaseTemplateType> GetRazorHostInAppDomain() { LocalAppDomain = CreateAppDomain(null); if (LocalAppDomain == null) return null; /// Create the instance inside of the new AppDomain /// Note: remote domain uses local EXE's AppBasePath!!! RazorEngine<TBaseTemplateType> host = null; try { Assembly ass = Assembly.GetExecutingAssembly(); string AssemblyPath = ass.Location; host = (RazorEngine<TBaseTemplateType>) LocalAppDomain.CreateInstanceFrom(AssemblyPath, typeof(RazorEngine<TBaseTemplateType>).FullName).Unwrap(); } catch (Exception ex) { ErrorMessage = ex.Message; return null; } return host; } /// <summary> /// Internally creates a new AppDomain in which Razor templates can /// be run. /// </summary> /// <param name="appDomainName"></param> /// <returns></returns> private AppDomain CreateAppDomain(string appDomainName) { if (appDomainName == null) appDomainName = "RazorHost_" + Guid.NewGuid().ToString("n"); AppDomainSetup setup = new AppDomainSetup(); // *** Point at current directory setup.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory; AppDomain localDomain = AppDomain.CreateDomain(appDomainName, null, setup); return localDomain; } /// <summary> /// Allow unloading of the created AppDomain to release resources /// All internal resources in the AppDomain are released including /// in memory compiled Razor assemblies. /// </summary> public void UnloadHost() { if (this.LocalAppDomain != null) { AppDomain.Unload(this.LocalAppDomain); this.LocalAppDomain = null; } } The static CreateRazorHostInAppDomain() is the key method that startup code usually calls. It uses a Current singleton instance to an instance of itself that is created cross AppDomain and is kept alive because it’s static. GetRazorHostInAppDomain actually creates a cross-AppDomain instance which first creates a new AppDomain and then loads the RazorEngine into it. The remote Proxy instance is returned as a result to the method and can be used the same as a local instance. The code to run with a remote AppDomain is simple: private RazorEngine<RazorTemplateBase> CreateHost() { if (this.Host != null) return this.Host; // Use Static Methods - no error message if host doesn't load this.Host = RazorEngineFactory<RazorTemplateBase>.CreateRazorHostInAppDomain(); if (this.Host == null) { MessageBox.Show("Unable to load Razor Template Host", "Razor Hosting", MessageBoxButtons.OK, MessageBoxIcon.Exclamation); } return this.Host; } This code relies on a local reference of the Host which is kept around for the duration of the app (in this case a form reference). To use this you’d simply do: this.Host = CreateHost(); if (host == null) return; string result = host.RenderTemplate( this.txtSource.Text, new string[] { "System.Windows.Forms.dll", "Westwind.Utilities.dll" }, this.CustomContext); if (result == null) { MessageBox.Show(host.ErrorMessage, "Template Execution Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation); return; } this.txtResult.Text = result; Now all templates run in a remote AppDomain and can be unloaded with simple code like this: RazorEngineFactory<RazorTemplateBase>.UnloadRazorHostInAppDomain(); this.Host = null; One Step further – Providing a caching ‘Runtime’ Once we can load templates in a remote AppDomain we can add some additional functionality like assembly caching based on application specific features. One of my typical scenarios is to render templates out of a scripts folder. So all templates live in a folder and they change infrequently. So a Folder based host that can compile these templates once and then only recompile them if something changes would be ideal. Enter host containers which are basically wrappers around the RazorEngine<t> and RazorEngineFactory<t>. They provide additional logic for things like file caching based on changes on disk or string hashes for string based template inputs. The folder host also provides for partial rendering logic through a custom template base implementation. There’s a base implementation in RazorBaseHostContainer, which provides the basics for hosting a RazorEngine, which includes the ability to start and stop the engine, cache assemblies and add references: public abstract class RazorBaseHostContainer<TBaseTemplateType> : MarshalByRefObject where TBaseTemplateType : RazorTemplateBase, new() { public RazorBaseHostContainer() { UseAppDomain = true; GeneratedNamespace = "__RazorHost"; } /// <summary> /// Determines whether the Container hosts Razor /// in a separate AppDomain. Seperate AppDomain /// hosting allows unloading and releasing of /// resources. /// </summary> public bool UseAppDomain { get; set; } /// <summary> /// Base folder location where the AppDomain /// is hosted. By default uses the same folder /// as the host application. /// /// Determines where binary dependencies are /// found for assembly references. /// </summary> public string BaseBinaryFolder { get; set; } /// <summary> /// List of referenced assemblies as string values. /// Must be in GAC or in the current folder of the host app/ /// base BinaryFolder /// </summary> public List<string> ReferencedAssemblies = new List<string>(); /// <summary> /// Name of the generated namespace for template classes /// </summary> public string GeneratedNamespace {get; set; } /// <summary> /// Any error messages /// </summary> public string ErrorMessage { get; set; } /// <summary> /// Cached instance of the Host. Required to keep the /// reference to the host alive for multiple uses. /// </summary> public RazorEngine<TBaseTemplateType> Engine; /// <summary> /// Cached instance of the Host Factory - so we can unload /// the host and its associated AppDomain. /// </summary> protected RazorEngineFactory<TBaseTemplateType> EngineFactory; /// <summary> /// Keep track of each compiled assembly /// and when it was compiled. /// /// Use a hash of the string to identify string /// changes. /// </summary> protected Dictionary<int, CompiledAssemblyItem> LoadedAssemblies = new Dictionary<int, CompiledAssemblyItem>(); /// <summary> /// Call to start the Host running. Follow by a calls to RenderTemplate to /// render individual templates. Call Stop when done. /// </summary> /// <returns>true or false - check ErrorMessage on false </returns> public virtual bool Start() { if (Engine == null) { if (UseAppDomain) Engine = RazorEngineFactory<TBaseTemplateType>.CreateRazorHostInAppDomain(); else Engine = RazorEngineFactory<TBaseTemplateType>.CreateRazorHost(); Engine.Configuration.CompileToMemory = true; Engine.HostContainer = this; if (Engine == null) { this.ErrorMessage = EngineFactory.ErrorMessage; return false; } } return true; } /// <summary> /// Stops the Host and releases the host AppDomain and cached /// assemblies. /// </summary> /// <returns>true or false</returns> public bool Stop() { this.LoadedAssemblies.Clear(); RazorEngineFactory<RazorTemplateBase>.UnloadRazorHostInAppDomain(); this.Engine = null; return true; } … } This base class provides most of the mechanics to host the runtime, but no application specific implementation for rendering. There are rendering functions but they just call the engine directly and provide no caching – there’s no context to decide how to cache and reuse templates. The key methods are Start and Stop and their main purpose is to start a new AppDomain (optionally) and shut it down when requested. The RazorFolderHostContainer – Folder Based Runtime Hosting Let’s look at the more application specific RazorFolderHostContainer implementation which is defined like this: public class RazorFolderHostContainer : RazorBaseHostContainer<RazorTemplateFolderHost> Note that a customized RazorTemplateFolderHost class template is used for this implementation that supports partial rendering in form of a RenderPartial() method that’s available to templates. The folder host’s features are: Render templates based on a Template Base Path (a ‘virtual’ if you will) Cache compiled assemblies based on the relative path and file time stamp File changes on templates cause templates to be recompiled into new assemblies Support for partial rendering using base folder relative pathing As shown in the startup examples earlier host containers require some startup code with a HostContainer tied to a persistent property (like a Form property): // The base path for templates - templates are rendered with relative paths // based on this path. HostContainer.TemplatePath = Path.Combine(Environment.CurrentDirectory, TemplateBaseFolder); // Default output rendering disk location HostContainer.RenderingOutputFile = Path.Combine(HostContainer.TemplatePath, "__Preview.htm"); // Add any assemblies you want reference in your templates HostContainer.ReferencedAssemblies.Add("System.Windows.Forms.dll"); // Start up the host container HostContainer.Start(); Once that’s done, you can render templates with the host container: // Pass the template path for full filename seleted with OpenFile Dialog // relativepath is: subdir\file.cshtml or file.cshtml or ..\file.cshtml var relativePath = Utilities.GetRelativePath(fileName, HostContainer.TemplatePath); if (!HostContainer.RenderTemplate(relativePath, Context, HostContainer.RenderingOutputFile)) { MessageBox.Show("Error: " + HostContainer.ErrorMessage); return; } webBrowser1.Navigate("file://" + HostContainer.RenderingOutputFile); The most critical task of the RazorFolderHostContainer implementation is to retrieve a template from disk, compile and cache it and then deal with deciding whether subsequent requests need to re-compile the template or simply use a cached version. Internally the GetAssemblyFromFileAndCache() handles this task: /// <summary> /// Internally checks if a cached assembly exists and if it does uses it /// else creates and compiles one. Returns an assembly Id to be /// used with the LoadedAssembly list. /// </summary> /// <param name="relativePath"></param> /// <param name="context"></param> /// <returns></returns> protected virtual CompiledAssemblyItem GetAssemblyFromFileAndCache(string relativePath) { string fileName = Path.Combine(TemplatePath, relativePath).ToLower(); int fileNameHash = fileName.GetHashCode(); if (!File.Exists(fileName)) { this.SetError(Resources.TemplateFileDoesnTExist + fileName); return null; } CompiledAssemblyItem item = null; this.LoadedAssemblies.TryGetValue(fileNameHash, out item); string assemblyId = null; // Check for cached instance if (item != null) { var fileTime = File.GetLastWriteTimeUtc(fileName); if (fileTime <= item.CompileTimeUtc) assemblyId = item.AssemblyId; } else item = new CompiledAssemblyItem(); // No cached instance - create assembly and cache if (assemblyId == null) { string safeClassName = GetSafeClassName(fileName); StreamReader reader = null; try { reader = new StreamReader(fileName, true); } catch (Exception ex) { this.SetError(Resources.ErrorReadingTemplateFile + fileName); return null; } assemblyId = Engine.ParseAndCompileTemplate(this.ReferencedAssemblies.ToArray(), reader); // need to ensure reader is closed if (reader != null) reader.Close(); if (assemblyId == null) { this.SetError(Engine.ErrorMessage); return null; } item.AssemblyId = assemblyId; item.CompileTimeUtc = DateTime.UtcNow; item.FileName = fileName; item.SafeClassName = safeClassName; this.LoadedAssemblies[fileNameHash] = item; } return item; } This code uses a LoadedAssembly dictionary which is comprised of a structure that holds a reference to a compiled assembly, a full filename and file timestamp and an assembly id. LoadedAssemblies (defined on the base class shown earlier) is essentially a cache for compiled assemblies and they are identified by a hash id. In the case of files the hash is a GetHashCode() from the full filename of the template. The template is checked for in the cache and if not found the file stamp is checked. If that’s newer than the cache’s compilation date the template is recompiled otherwise the version in the cache is used. All the core work defers to a RazorEngine<T> instance to ParseAndCompileTemplate(). The three rendering specific methods then are rather simple implementations with just a few lines of code dealing with parameter and return value parsing: /// <summary> /// Renders a template to a TextWriter. Useful to write output into a stream or /// the Response object. Used for partial rendering. /// </summary> /// <param name="relativePath">Relative path to the file in the folder structure</param> /// <param name="context">Optional context object or null</param> /// <param name="writer">The textwriter to write output into</param> /// <returns></returns> public bool RenderTemplate(string relativePath, object context, TextWriter writer) { // Set configuration data that is to be passed to the template (any object) Engine.TemplatePerRequestConfigurationData = new RazorFolderHostTemplateConfiguration() { TemplatePath = Path.Combine(this.TemplatePath, relativePath), TemplateRelativePath = relativePath, }; CompiledAssemblyItem item = GetAssemblyFromFileAndCache(relativePath); if (item == null) { writer.Close(); return false; } try { // String result will be empty as output will be rendered into the // Response object's stream output. However a null result denotes // an error string result = Engine.RenderTemplateFromAssembly(item.AssemblyId, context, writer); if (result == null) { this.SetError(Engine.ErrorMessage); return false; } } catch (Exception ex) { this.SetError(ex.Message); return false; } finally { writer.Close(); } return true; } /// <summary> /// Render a template from a source file on disk to a specified outputfile. /// </summary> /// <param name="relativePath">Relative path off the template root folder. Format: path/filename.cshtml</param> /// <param name="context">Any object that will be available in the template as a dynamic of this.Context</param> /// <param name="outputFile">Optional - output file where output is written to. If not specified the /// RenderingOutputFile property is used instead /// </param> /// <returns>true if rendering succeeds, false on failure - check ErrorMessage</returns> public bool RenderTemplate(string relativePath, object context, string outputFile) { if (outputFile == null) outputFile = RenderingOutputFile; try { using (StreamWriter writer = new StreamWriter(outputFile, false, Engine.Configuration.OutputEncoding, Engine.Configuration.StreamBufferSize)) { return RenderTemplate(relativePath, context, writer); } } catch (Exception ex) { this.SetError(ex.Message); return false; } return true; } /// <summary> /// Renders a template to string. Useful for RenderTemplate /// </summary> /// <param name="relativePath"></param> /// <param name="context"></param> /// <returns></returns> public string RenderTemplateToString(string relativePath, object context) { string result = string.Empty; try { using (StringWriter writer = new StringWriter()) { // String result will be empty as output will be rendered into the // Response object's stream output. However a null result denotes // an error if (!RenderTemplate(relativePath, context, writer)) { this.SetError(Engine.ErrorMessage); return null; } result = writer.ToString(); } } catch (Exception ex) { this.SetError(ex.Message); return null; } return result; } The idea is that you can create custom host container implementations that do exactly what you want fairly easily. Take a look at both the RazorFolderHostContainer and RazorStringHostContainer classes for the basic concepts you can use to create custom implementations. Notice also that you can set the engine’s PerRequestConfigurationData() from the host container: // Set configuration data that is to be passed to the template (any object) Engine.TemplatePerRequestConfigurationData = new RazorFolderHostTemplateConfiguration() { TemplatePath = Path.Combine(this.TemplatePath, relativePath), TemplateRelativePath = relativePath, }; which when set to a non-null value is passed to the Template’s InitializeTemplate() method. This method receives an object parameter which you can cast as needed: public override void InitializeTemplate(object configurationData) { // Pick up configuration data and stuff into Request object RazorFolderHostTemplateConfiguration config = configurationData as RazorFolderHostTemplateConfiguration; this.Request.TemplatePath = config.TemplatePath; this.Request.TemplateRelativePath = config.TemplateRelativePath; } With this data you can then configure any custom properties or objects on your main template class. It’s an easy way to pass data from the HostContainer all the way down into the template. The type you use is of type object so you have to cast it yourself, and it must be serializable since it will likely run in a separate AppDomain. This might seem like an ugly way to pass data around – normally I’d use an event delegate to call back from the engine to the host, but since this is running over AppDomain boundaries events get really tricky and passing a template instance back up into the host over AppDomain boundaries doesn’t work due to serialization issues. So it’s easier to pass the data from the host down into the template using this rather clumsy approach of set and forward. It’s ugly, but it’s something that can be hidden in the host container implementation as I’ve done here. It’s also not something you have to do in every implementation so this is kind of an edge case, but I know I’ll need to pass a bunch of data in some of my applications and this will be the easiest way to do so. Summing Up Hosting the Razor runtime is something I got jazzed up about quite a bit because I have an immediate need for this type of templating/merging/scripting capability in an application I’m working on. I’ve also been using templating in many apps and it’s always been a pain to deal with. The Razor engine makes this whole experience a lot cleaner and more light weight and with these wrappers I can now plug .NET based templating into my code literally with a few lines of code. That’s something to cheer about… I hope some of you will find this useful as well… Resources The examples and code require that you download the Razor runtimes. Projects are for Visual Studio 2010 running on .NET 4.0 Platform Installer 3.0 (install WebMatrix or MVC 3 for Razor Runtimes) Latest Code in Subversion Repository Download Snapshot of the Code Documentation (CHM Help File) © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET .NET

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Tools and Utilities for the .NET Developer

- by mbcrump

Tweet this list! Add a link to my site to your bookmarks to quickly find this page again! Add me to twitter! This is a list of the tools/utilities that I use to do my job/hobby. I wanted this page to load fast and contain information that only you care about. If I have missed a tool that you like, feel free to contact me and I will add it to the list. Also, this list took a lot of time to complete. Please do not steal my work, if you like the page then please link back to my site. I will keep the links/information updated as new tools/utilities are created. Windows/.NET Development – This is a list of tools that any Windows/.NET developer should have in his bag. I have used at some point in my career everything listed on this page and below is the tools worth keeping. Name Description License AnkhSVN Subversion support for Visual Studio. It also works with VS2010. Free Aurora XAML Designer One of the best XAML creation tools available. Has a ton of built in templates that you can copy/paste into VS2010. COST/Trial BeyondCompare Beyond Compare 3 is the ideal tool for comparing files and folders on your Windows or Linux system. Visualize changes in your code and carefully reconcile them. COST/Trial BuildIT Automated Task Tool Its main purpose is to automate tasks, whether it is the final packaging of a product, an automated daily build, maybe sending out a mailing list, even backing-up files. Free C Sharper for VB Convert VB to C#. COST CLRProfiler Analyze and improve the behavior of your .NET app. Free CodeRush Direct competitor to ReSharper, contains similar feature. This is one of those decide for yourself. COST/Trial Disk2VHD Disk2vhd is a utility that creates VHD (Virtual Hard Disk - Microsoft's Virtual Machine disk format) versions of physical disks for use in Microsoft Virtual PC or Microsoft Hyper-V virtual machines (VMs). Free Eazfuscator.NET Is a free obfuscator for .NET. The main purpose is to protect intellectual property of software. Free EQATEC Profiler Make your .NET app run faster. No source code changes are needed. Just point the profiler to your app, run the modified code, and get a visual report. COST Expression Studio 3/4 Comes with Web, Blend, Sketch Flow and more. You can create websites, produce beautiful XAML and more. COST/Trial Expresso The award-winning Expresso editor is equally suitable as a teaching tool for the beginning user of regular expressions or as a full-featured development environment for the experienced programmer or web designer with an extensive knowledge of regular expressions. Free Fiddler Fiddler is a web debugging proxy which logs all HTTP(s) traffic between your computer and the internet. Free Firebug Powerful Web development tool. If you build websites, you will need this. Free FxCop FxCop is an application that analyzes managed code assemblies (code that targets the .NET Framework common language runtime) and reports information about the assemblies, such as possible design, localization, performance, and security improvements. Free GAC Browser and Remover Easy way to remove multiple assemblies from the GAC. Assemblies registered by programs like Install Shield can also be removed. Free GAC Util The Global Assembly Cache tool allows you to view and manipulate the contents of the global assembly cache and download cache. Free HelpScribble Help Scribble is a full-featured, easy-to-use help authoring tool for creating help files from start to finish. You can create Win Help (.hlp) files, HTML Help (.chm) files, a printed manual and online documentation (on a web site) all from the same Help Scribble project. COST/Trial IETester IETester is a free Web Browser that allows you to have the rendering and JavaScript engines of IE9 preview, IE8, IE7 IE 6 and IE5.5 on Windows 7, Vista and XP, as well as the installed IE in the same process. Free iTextSharp iText# (iTextSharp) is a port of the iText open source java library for PDF generation written entirely in C# for the .NET platform. Use the iText mailing list to get support. Free Kaxaml Kaxaml is a lightweight XAML editor that gives you a "split view" so you can see both your XAML and your rendered content. Free LINQPad LinqPad lets you interactively query databases in a LINQ. Free Linquer Many programmers are familiar with SQL and will need a help in the transition to LINQ. Sometimes there are complicated queries to be written and Linqer can help by converting SQL scripts to LINQ. COST/Trial LiquidXML Liquid XML Studio 2010 is an advanced XML developers toolkit and IDE, containing all the tools needed for designing and developing XML schema and applications. COST/Trial Log4Net log4net is a tool to help the programmer output log statements to a variety of output targets. log4net is a port of the excellent log4j framework to the .NET runtime. We have kept the framework similar in spirit to the original log4j while taking advantage of new features in the .NET runtime. For more information on log4net see the features document. Free Microsoft Web Platform Installer The Microsoft Web Platform Installer 2.0 (Web PI) is a free tool that makes getting the latest components of the Microsoft Web Platform, including Internet Information Services (IIS), SQL Server Express, .NET Framework and Visual Web Developer easy. Free Mono Development Don't have Visual Studio - no problem! This is an open Source C# and .NET development environment for Linux, Windows, and Mac OS X Free Net Mass Downloader While it’s great that Microsoft has released the .NET Reference Source Code, you can only get it one file at a time while you’re debugging. If you’d like to batch download it for reading or to populate the cache, you’d have to write a program that instantiated and called each method in the Framework Class Library. Fortunately, .NET Mass Downloader comes to the rescue! Free nMap Nmap ("Network Mapper") is a free and open source (license) utility for network exploration or security auditing. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime. Free NoScript (Firefox add-in) The NoScript Firefox extension provides extra protection for Firefox, Flock, Seamonkey and other Mozilla-based browsers: this free, open source add-on allows JavaScript, Java and Flash and other plug-ins to be executed only by trusted web sites of your choice (e.g. your online bank), and provides the most powerful Anti-XSS protection available in a browser. Free NotePad 2 Notepad2, a fast and light-weight Notepad-like text editor with syntax highlighting. This program can be run out of the box without installation, and does not touch your system's registry. Free PageSpy PageSpy is a small add-on for Internet Explorer that allows you to select any element within a webpage, select an option in the context menu, and view detailed information about both the coding behind the page and the element you selected. Free Phrase Express PhraseExpress manages your frequently used text snippets in customizable categories for quick access. Free PowerGui PowerGui is a free community for PowerGUI, a graphical user interface and script editor for Microsoft Windows PowerShell! Free Powershell Comes with Win7, but you can automate tasks by using the .NET Framework. Great for network admins. Free Process Explorer Ever wondered which program has a particular file or directory open? Now you can find out. Process Explorer shows you information about which handles and DLLs processes have opened or loaded. Also, included in the SysInterals Suite. Free Process Monitor Process Monitor is an advanced monitoring tool for Windows that shows real-time file system, Registry and process/thread activity. Free Reflector Explore and analyze compiled .NET assemblies, viewing them in C#, Visual Basic, and IL. This is an Essential for any .NET developer. Free Regular Expression Library Stuck on a Regular Expression but you think someone has already figured it out? Chances are they have. Free Regulator Regulator makes Regular Expressions easy. This is a must have for a .NET Developer. Free RenameMaestro RenameMaestro is probably the easiest batch file renamer you'll find to instantly rename multiple files COST ReSharper The one program that I cannot live without. Supports VS2010 and offers simple refactoring, code analysis/assistance/cleanup/templates. One of the few applications that is worth the $$$. COST/Trial ScrewTurn Wiki ScrewTurn Wiki allows you to create, manage and share wikis. A wiki is a collaboratively-edited, information-centered website: the most famous is Wikipedia. Free SharpDevelop What is #develop? SharpDevelop is a free IDE for C# and VB.NET projects on Microsoft's .NET platform. Free Show Me The Template Show Me The Template is a tool for exploring the templates, be their data, control or items panel, that comes with the controls built into WPF for all 6 themes. Free SnippetCompiler Compiles code snippets without opening Visual Studio. It does not support .NET 4. Free SQL Prompt SQL Prompt is a plug-in that increases how fast you can work with SQL. It provides code-completion for SQL server, reformatting, db schema information and snippets. Awesome! COST/Trial SQLinForm SQLinForm is an automatic SQL code formatter for all major databases including ORACLE, SQL Server, DB2, UDB, Sybase, Informix, PostgreSQL, Teradata, MySQL, MS Access etc. with over 70 formatting options. COST/OnlineFree SSMS Tools SSMS Tools Pack is an add-in for Microsoft SQL Server Management Studio (SSMS) including SSMS Express. Free Storm STORM is a free and open source tool for testing web services. Free Telerik Code Convertor Convert code from VB to C Sharp and Vice Versa. Free TurtoiseSVN TortoiseSVN is a really easy to use Revision control / version control / source control software for Windows.Since it's not an integration for a specific IDE you can use it with whatever development tools you like. Free UltraEdit UltraEdit is the ideal text, HTML and hex editor, and an advanced PHP, Perl, Java and JavaScript editor for programmers. UltraEdit is also an XML editor including a tree-style XML parser. An industry-award winner, UltraEdit supports disk-based 64-bit file handling (standard) on 32-bit Windows platforms (Windows 2000 and later). COST/Trial Virtual Windows XP Comes with some W7 version and allows you to run WinXP along side W7. Free VirtualBox Virtualization by Sun Microsystems. You can virtualize Windows, Linux and more. Free Visual Log Parser SQL queries against a variety of log files and other system data sources. Free WinMerge WinMerge is an Open Source differencing and merging tool for Windows. WinMerge can compare both folders and files, presenting differences in a visual text format that is easy to understand and handle. Free Wireshark Wireshark is one of the best network protocol analyzer's for Unix and windows. This has been used several times to get me out of a bind. Free XML Notepad 07 Old, but still one of my favorite XML viewers. Free Productivity Tools – This is the list of tools that I use to save time or quickly navigate around Windows. Name Description License AutoHotKey Automate almost anything by sending keystrokes and mouse clicks. You can write a mouse or keyboard macro by hand or use the macro recorder. Free CLCL CLCL is clipboard caching utility. Free Ditto Ditto is an extension to the standard windows clipboard. It saves each item placed on the clipboard allowing you access to any of those items at a later time. Ditto allows you to save any type of information that can be put on the clipboard, text, images, html, custom formats, ..... Free Evernote Remember everything from notes to photos. It will synch between computers/devices. Free InfoRapid Inforapid is a search tool that will display all you search results in a html like browser. If you click on a word in that browser, it will start another search to the word you clicked on. Handy if you want to trackback something to it's true origin. The word you looked for will be highlighted in red. Clicking on the red word will open the containing file in a text based viewer. Clicking on any word in the opened document will start another search on that word. Free KatMouse The prime purpose of the KatMouse utility is to enhance the functionality of mice with a scroll wheel, offering 'universal' scrolling: moving the mouse wheel will scroll the window directly beneath the mouse cursor (not the one with the keyboard focus, which is default on Windows OSes). This is a major increase in the usefulness of the mouse wheel. Free ScreenR Instant Screencast with nothing to download. Works with Mac or PC and free. Free Start++ Start++ is an enhancement for the Start Menu in Windows Vista. It also extends the Run box and the command-line with customizable commands. For example, typing "w Windows Vista" will take you to the Windows Vista page on Wikipedia! Free Synergy Synergy lets you easily share a single mouse and keyboard between multiple computers with different operating systems, each with its own display, without special hardware. It's intended for users with multiple computers on their desk since each system uses its own monitor(s). Free Texter Texter lets you define text substitution hot strings that, when triggered, will replace hotstring with a larger piece of text. By entering your most commonly-typed snippets of text into Texter, you can save countless keystrokes in the course of the day. Free Total Commander File handling, FTP, Archive handling and much more. Even works with Win3.11. COST/Trial Available Wizmouse WizMouse is a mouse enhancement utility that makes your mouse wheel work on the window currently under the mouse pointer, instead of the currently focused window. This means you no longer have to click on a window before being able to scroll it with the mouse wheel. This is a far more comfortable and practical way to make use of the mouse wheel. Free Xmarks Bookmark sync and search between computers. Free General Utilities – This is a list for power user users or anyone that wants more out of Windows. I usually install a majority of these whenever I get a new system. Name Description License µTorrent µTorrent is a lightweight and efficient BitTorrent client for Windows or Mac with many features. I use this for downloading LEGAL media. Free Audacity Audacity® is free, open source software for recording and editing sounds. It is available for Mac OS X, Microsoft Windows, GNU/Linux, and other operating systems. Learn more about Audacity... Also check our Wiki and Forum for more information. Free AVast Free FREE Antivirus. Free CD Burner XP Pro CDBurnerXP is a free application to burn CDs and DVDs, including Blu-Ray and HD-DVDs. It also includes the feature to burn and create ISOs, as well as a multilanguage interface. Free CDEX You can extract digital audio CDs into mp3/wav. Free Combofix Combofix is a freeware (a legitimate spyware remover created by sUBs), Combofix was designed to scan a computer for known malware, spyware (SurfSideKick, QooLogic, and Look2Me as well as any other combination of the mentioned spyware applications) and remove them. Free Cpu-Z Provides information about some of the main devices of your system. Free Cropper Cropper is a screen capture utility written in C#. It makes it fast and easy to grab parts of your screen. Use it to easily crop out sections of vector graphic files such as Fireworks without having to flatten the files or open in a new editor. Use it to easily capture parts of a web site, including text and images. It's also great for writing documentation that needs images of your application or web site. Free DropBox Drag and Drop files to sync between computers. Free DVD-Fab Converts/Copies DVDs/Blu-Ray to different formats. (like mp4, mkv, avi) COST/Trial Available FastStone Capture FastStone Capture is a powerful, lightweight, yet full-featured screen capture tool that allows you to easily capture and annotate anything on the screen including windows, objects, menus, full screen, rectangular/freehand regions and even scrolling windows/web pages. Free ffdshow FFDShow is a DirectShow decoding filter for decompressing DivX, XviD, H.264, FLV1, WMV, MPEG-1 and MPEG-2, MPEG-4 movies. Free Filezilla FileZilla Client is a fast and reliable cross-platform FTP, FTPS and SFTP client with lots of useful features and an intuitive graphical user interface. You can also download a server version. Free FireFox Web Browser, do you really need an explanation? Free FireGestures A customizable mouse gestures extension which enables you to execute various commands and user scripts with five types of gestures. Free FoxIt Reader Light weight PDF viewer. You should install this with the advanced setting or it will install a toolbar and setup some shortcuts. Free gSynchIt Synch Gmail and Outlook. Even supports Outlook 2010 32/64 bit COST/Trial Available Hulu Desktop At home or in a hotel, this has replaced my cable/satellite subscription. Free ImgBurn ImgBurn is a lightweight CD / DVD / HD DVD / Blu-ray burning application that everyone should have in their toolkit! Free Infrarecorder InfraRecorder is a free CD/DVD burning solution for Microsoft Windows. It offers a wide range of powerful features; all through an easy to use application interface and Windows Explorer integration. Free KeePass KeePass is a free open source password manager, which helps you to manage your passwords in a secure way. Free LastPass Another password management, synchronize between browsers, automatic form filling and more. Free Live Essentials One download and lots of programs including Mail, Live Writer, Movie Maker and more! Free Monitores MonitorES is a small windows utility that helps you to turnoff monitor display when you lock down your machine.Also when you lock your machine, it will pause all your running media programs & set your IM status message to "Away" / Custom message(via options) and restore it back to normal when you back. Free mRemote mRemote is a full-featured, multi-tab remote connections manager. Free Open Office OpenOffice.org 3 is the leading open-source office software suite for word processing, spreadsheets, presentations, graphics, databases and more. It is available in many languages and works on all common computers. It stores all your data in an international open standard format and can also read and write files from other common office software packages. It can be downloaded and used completely free of charge for any purpose. Free Paint.NET Simple, intuitive, and innovative user interface for editing photos. Free Picasa Picasa is free photo editing software from Google that makes your pictures look great. Free Pidgin Pidgin is an easy to use and free chat client used by millions. Connect to AIM, MSN, Yahoo, and more chat networks all at once. Free PING PING is a live Linux ISO, based on the excellent Linux From Scratch (LFS) documentation. It can be burnt on a CD and booted, or integrated into a PXE / RIS environment. Free Putty PuTTY is an SSH and telnet client, developed originally by Simon Tatham for the Windows platform. Free Revo Uninstaller Revo Uninstaller Pro helps you to uninstall software and remove unwanted programs installed on your computer easily! Even if you have problems uninstalling and cannot uninstall them from "Windows Add or Remove Programs" control panel applet.Revo Uninstaller is a much faster and more powerful alternative to "Windows Add or Remove Programs" applet! It has very powerful features to uninstall and remove programs. Free Security Essentials Microsoft Security Essentials is a new, free consumer anti-malware solution for your computer. Free SetupVirtualCloneDrive Virtual CloneDrive works and behaves just like a physical CD/DVD drive, however it exists only virtually. Point to the .ISO file and it appears in Windows Explorer as a Drive. Free Shark 007 Codec Pack Play just about any file format with this download. Also includes my W7 Media Playlist Generator. Free Snagit 9 Screen Capture on steroids. Add arrows, captions, etc to any screenshot. COST/Trial Available SysinternalsSuite Go ahead and download the entire sys internals suite. I have mentioned multiple programs in this suite already. Free TeraCopy TeraCopy is a compact program designed to copy and move files at the maximum possible speed, providing the user with a lot of features. Free for Home TrueCrypt Free open-source disk encryption software for Windows 7/Vista/XP, Mac OS X, and Linux Free TweetDeck Fully featured Twitter client. Free UltraVNC UltraVNC is a powerful, easy to use and free software that can display the screen of another computer (via internet or network) on your own screen. The program allows you to use your mouse and keyboard to control the other PC remotely. It means that you can work on a remote computer, as if you were sitting in front of it, right from your current location. Free Unlocker Unlocks locked files. Pretty simple right? Free VLC Media Player VLC media player is a highly portable multimedia player and multimedia framework capable of reading most audio and video formats Free Windows 7 Media Playlist This program is special to my heart because I wrote it. It has been mentioned on podcast and various websites. It allows you to quickly create wvx video playlist for Windows Media Center. Free WinRAR WinRAR is a powerful archive manager. It can backup your data and reduce the size of email attachments, decompress RAR, ZIP and other files downloaded from Internet and create new archives in RAR and ZIP file format. COST/Trial Available Blogging – I use the following for my blog. Name Description License Insert Code for Windows Live Writer Insert Code for Windows Live Writer will format a snippet of text in a number of programming languages such as C#, HTML, MSH, JavaScript, Visual Basic and TSQL. Free LiveWriter Included in Live Essentials, but the ultimate in Windows Blogging Free PasteAsVSCode Plug-in for Windows Live Writer that pastes clipboard content as Visual Studio code. Preserves syntax highlighting, indentation and background color. Converts RTF, outputted by Visual Studio, into HTML. Free Desktop Management – The list below represent the best in Windows Desktop Management. Name Description License 7 Stacks Allows users to have "stacks" of icons in their taskbar. Free Executor Executor is a multi purpose launcher and a more advanced and customizable version of windows run. Free Fences Fences is a program that helps you organize your desktop and can hide your icons when they are not in use. Free RocketDock Rocket Dock is a smoothly animated, alpha blended application launcher. It provides a nice clean interface to drop shortcuts on for easy access and organization. With each item completely customizable there is no end to what you can add and launch from the dock. Free WindowsTab Tabbing is an essential feature of modern web browsers. Window Tabs brings the productivity of tabbed window management to all of your desktop applications. Free

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Is there a Telecommunications Reference Architecture?

- by raul.goycoolea

@font-face { font-family: "Arial"; }@font-face { font-family: "Courier New"; }@font-face { font-family: "Wingdings"; }@font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }div.Section1 { page: Section1; }ol { margin-bottom: 0cm; }ul { margin-bottom: 0cm; } Abstract Reference architecture provides needed architectural information that can be provided in advance to an enterprise to enable consistent architectural best practices. Enterprise Reference Architecture helps business owners to actualize their strategies, vision, objectives, and principles. It evaluates the IT systems, based on Reference Architecture goals, principles, and standards. It helps to reduce IT costs by increasing functionality, availability, scalability, etc. Telecom Reference Architecture provides customers with the flexibility to view bundled service bills online with the provision of multiple services. It provides real-time, flexible billing and charging systems, to handle complex promotions, discounts, and settlements with multiple parties. This paper attempts to describe the Reference Architecture for the Telecom Enterprises. It lays the foundation for a Telecom Reference Architecture by articulating the requirements, drivers, and pitfalls for telecom service providers. It describes generic reference architecture for telecom enterprises and moves on to explain how to achieve Enterprise Reference Architecture by using SOA. Introduction A Reference Architecture provides a methodology, set of practices, template, and standards based on a set of successful solutions implemented earlier. These solutions have been generalized and structured for the depiction of both a logical and a physical architecture, based on the harvesting of a set of patterns that describe observations in a number of successful implementations. It helps as a reference for the various architectures that an enterprise can implement to solve various problems. It can be used as the starting point or the point of comparisons for various departments/business entities of a company, or for the various companies for an enterprise. It provides multiple views for multiple stakeholders. Major artifacts of the Enterprise Reference Architecture are methodologies, standards, metadata, documents, design patterns, etc. Purpose of Reference Architecture In most cases, architects spend a lot of time researching, investigating, defining, and re-arguing architectural decisions. It is like reinventing the wheel as their peers in other organizations or even the same organization have already spent a lot of time and effort defining their own architectural practices. This prevents an organization from learning from its own experiences and applying that knowledge for increased effectiveness. Reference architecture provides missing architectural information that can be provided in advance to project team members to enable consistent architectural best practices. Enterprise Reference Architecture helps an enterprise to achieve the following at the abstract level: · Reference architecture is more of a communication channel to an enterprise · Helps the business owners to accommodate to their strategies, vision, objectives, and principles. · Evaluates the IT systems based on Reference Architecture Principles · Reduces IT spending through increasing functionality, availability, scalability, etc · A Real-time Integration Model helps to reduce the latency of the data updates Is used to define a single source of Information · Provides a clear view on how to manage information and security · Defines the policy around the data ownership, product boundaries, etc. · Helps with cost optimization across project and solution portfolios by eliminating unused or duplicate investments and assets · Has a shorter implementation time and cost Once the reference architecture is in place, the set of architectural principles, standards, reference models, and best practices ensure that the aligned investments have the greatest possible likelihood of success in both the near term and the long term (TCO). Common pitfalls for Telecom Service Providers Telecom Reference Architecture serves as the first step towards maturity for a telecom service provider. During the course of our assignments/experiences with telecom players, we have come across the following observations – Some of these indicate a lack of maturity of the telecom service provider: · In markets that are growing and not so mature, it has been observed that telcos have a significant amount of in-house or home-grown applications. In some of these markets, the growth has been so rapid that IT has been unable to cope with business demands. Telcos have shown a tendency to come up with workarounds in their IT applications so as to meet business needs. · Even for core functions like provisioning or mediation, some telcos have tried to manage with home-grown applications. · Most of the applications do not have the required scalability or maintainability to sustain growth in volumes or functionality. · Applications face interoperability issues with other applications in the operator's landscape. Integrating a new application or network element requires considerable effort on the part of the other applications. · Application boundaries are not clear, and functionality that is not in the initial scope of that application gets pushed onto it. This results in the development of the multiple, small applications without proper boundaries. · Usage of Legacy OSS/BSS systems, poor Integration across Multiple COTS Products and Internal Systems. Most of the Integrations are developed on ad-hoc basis and Point-to-Point Integration. · Redundancy of the business functions in different applications • Fragmented data across the different applications and no integrated view of the strategic data • Lot of performance Issues due to the usage of the complex integration across OSS and BSS systems However, this is where the maturity of the telecom industry as a whole can be of help. The collaborative efforts of telcos to overcome some of these problems have resulted in bodies like the TM Forum. They have come up with frameworks for business processes, data, applications, and technology for telecom service providers. These could be a good starting point for telcos to clean up their enterprise landscape. Industry Trends in Telecom Reference Architecture Telecom reference architectures are evolving rapidly because telcos are facing business and IT challenges. “The reality is that there probably is no killer application, no silver bullet that the telcos can latch onto to carry them into a 21st Century.... Instead, there are probably hundreds – perhaps thousands – of niche applications.... And the only way to find which of these works for you is to try out lots of them, ramp up the ones that work, and discontinue the ones that fail.” – Martin Creaner President & CTO TM Forum. The following trends have been observed in telecom reference architecture: · Transformation of business structures to align with customer requirements · Adoption of more Internet-like technical architectures. The Web 2.0 concept is increasingly being used. · Virtualization of the traditional operations support system (OSS) · Adoption of SOA to support development of IP-based services · Adoption of frameworks like Service Delivery Platforms (SDPs) and IP Multimedia Subsystem · (IMS) to enable seamless deployment of various services over fixed and mobile networks · Replacement of in-house, customized, and stove-piped OSS/BSS with standards-based COTS products · Compliance with industry standards and frameworks like eTOM, SID, and TAM to enable seamless integration with other standards-based products Drivers of Reference Architecture The drivers of the Reference Architecture are Reference Architecture Goals, Principles, and Enterprise Vision and Telecom Transformation. The details are depicted below diagram. @font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoCaption, li.MsoCaption, div.MsoCaption { margin: 0cm 0cm 10pt; font-size: 9pt; font-family: "Times New Roman"; color: rgb(79, 129, 189); font-weight: bold; }div.Section1 { page: Section1; } Figure 1. Drivers for Reference Architecture @font-face { font-family: "Arial"; }@font-face { font-family: "Courier New"; }@font-face { font-family: "Wingdings"; }@font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }div.Section1 { page: Section1; }ol { margin-bottom: 0cm; }ul { margin-bottom: 0cm; } Today’s telecom reference architectures should seamlessly integrate traditional legacy-based applications and transition to next-generation network technologies (e.g., IP multimedia subsystems). This has resulted in new requirements for flexible, real-time billing and OSS/BSS systems and implications on the service provider’s organizational requirements and structure. Telecom reference architectures are today expected to: · Integrate voice, messaging, email and other VAS over fixed and mobile networks, back end systems · Be able to provision multiple services and service bundles • Deliver converged voice, video and data services · Leverage the existing Network Infrastructure · Provide real-time, flexible billing and charging systems to handle complex promotions, discounts, and settlements with multiple parties. · Support charging of advanced data services such as VoIP, On-Demand, Services (e.g. Video), IMS/SIP Services, Mobile Money, Content Services and IPTV. · Help in faster deployment of new services • Serve as an effective platform for collaboration between network IT and business organizations · Harness the potential of converging technology, networks, devices and content to develop multimedia services and solutions of ever-increasing sophistication on a single Internet Protocol (IP) · Ensure better service delivery and zero revenue leakage through real-time balance and credit management · Lower operating costs to drive profitability Enterprise Reference Architecture The Enterprise Reference Architecture (RA) fills the gap between the concepts and vocabulary defined by the reference model and the implementation. Reference architecture provides detailed architectural information in a common format such that solutions can be repeatedly designed and deployed in a consistent, high-quality, supportable fashion. This paper attempts to describe the Reference Architecture for the Telecom Application Usage and how to achieve the Enterprise Level Reference Architecture using SOA. • Telecom Reference Architecture • Enterprise SOA based Reference Architecture Telecom Reference Architecture Tele Management Forum’s New Generation Operations Systems and Software (NGOSS) is an architectural framework for organizing, integrating, and implementing telecom systems. NGOSS is a component-based framework consisting of the following elements: · The enhanced Telecom Operations Map (eTOM) is a business process framework. · The Shared Information Data (SID) model provides a comprehensive information framework that may be specialized for the needs of a particular organization. · The Telecom Application Map (TAM) is an application framework to depict the functional footprint of applications, relative to the horizontal processes within eTOM. · The Technology Neutral Architecture (TNA) is an integrated framework. TNA is an architecture that is sustainable through technology changes. NGOSS Architecture Standards are: · Centralized data · Loosely coupled distributed systems · Application components/re-use · A technology-neutral system framework with technology specific implementations · Interoperability to service provider data/processes · Allows more re-use of business components across multiple business scenarios · Workflow automation The traditional operator systems architecture consists of four layers, · Business Support System (BSS) layer, with focus toward customers and business partners. Manages order, subscriber, pricing, rating, and billing information. · Operations Support System (OSS) layer, built around product, service, and resource inventories. · Networks layer – consists of Network elements and 3rd Party Systems. · Integration Layer – to maximize application communication and overall solution flexibility. Reference architecture for telecom enterprises is depicted below. @font-face { font-family: "Arial"; }@font-face { font-family: "Courier New"; }@font-face { font-family: "Wingdings"; }@font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoCaption, li.MsoCaption, div.MsoCaption { margin: 0cm 0cm 10pt; font-size: 9pt; font-family: "Times New Roman"; color: rgb(79, 129, 189); font-weight: bold; }p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }div.Section1 { page: Section1; }ol { margin-bottom: 0cm; }ul { margin-bottom: 0cm; } Figure 2. Telecom Reference Architecture The major building blocks of any Telecom Service Provider architecture are as follows: 1. Customer Relationship Management CRM encompasses the end-to-end lifecycle of the customer: customer initiation/acquisition, sales, ordering, and service activation, customer care and support, proactive campaigns, cross sell/up sell, and retention/loyalty. CRM also includes the collection of customer information and its application to personalize, customize, and integrate delivery of service to a customer, as well as to identify opportunities for increasing the value of the customer to the enterprise. The key functionalities related to Customer Relationship Management are · Manage the end-to-end lifecycle of a customer request for products. · Create and manage customer profiles. · Manage all interactions with customers – inquiries, requests, and responses. · Provide updates to Billing and other south bound systems on customer/account related updates such as customer/ account creation, deletion, modification, request bills, final bill, duplicate bills, credit limits through Middleware. · Work with Order Management System, Product, and Service Management components within CRM. · Manage customer preferences – Involve all the touch points and channels to the customer, including contact center, retail stores, dealers, self service, and field service, as well as via any media (phone, face to face, web, mobile device, chat, email, SMS, mail, the customer's bill, etc.). · Support single interface for customer contact details, preferences, account details, offers, customer premise equipment, bill details, bill cycle details, and customer interactions. CRM applications interact with customers through customer touch points like portals, point-of-sale terminals, interactive voice response systems, etc. The requests by customers are sent via fulfillment/provisioning to billing system for ordering processing. 2. Billing and Revenue Management Billing and Revenue Management handles the collection of appropriate usage records and production of timely and accurate bills – for providing pre-bill usage information and billing to customers; for processing their payments; and for performing payment collections. In addition, it handles customer inquiries about bills, provides billing inquiry status, and is responsible for resolving billing problems to the customer's satisfaction in a timely manner. This process grouping also supports prepayment for services. The key functionalities provided by these applications are · To ensure that enterprise revenue is billed and invoices delivered appropriately to customers. · To manage customers’ billing accounts, process their payments, perform payment collections, and monitor the status of the account balance. · To ensure the timely and effective fulfillment of all customer bill inquiries and complaints. · Collect the usage records from mediation and ensure appropriate rating and discounting of all usage and pricing. · Support revenue sharing; split charging where usage is guided to an account different from the service consumer. · Support prepaid and post-paid rating. · Send notification on approach / exceeding the usage thresholds as enforced by the subscribed offer, and / or as setup by the customer. · Support prepaid, post paid, and hybrid (where some services are prepaid and the rest of the services post paid) customers and conversion from post paid to prepaid, and vice versa. · Support different billing function requirements like charge prorating, promotion, discount, adjustment, waiver, write-off, account receivable, GL Interface, late payment fee, credit control, dunning, account or service suspension, re-activation, expiry, termination, contract violation penalty, etc. · Initiate direct debit to collect payment against an invoice outstanding. · Send notification to Middleware on different events; for example, payment receipt, pre-suspension, threshold exceed, etc. Billing systems typically get usage data from mediation systems for rating and billing. They get provisioning requests from order management systems and inquiries from CRM systems. Convergent and real-time billing systems can directly get usage details from network elements. 3. Mediation Mediation systems transform/translate the Raw or Native Usage Data Records into a general format that is acceptable to billing for their rating purposes. The following lists the high-level roles and responsibilities executed by the Mediation system in the end-to-end solution. · Collect Usage Data Records from different data sources – like network elements, routers, servers – via different protocol and interfaces. · Process Usage Data Records – Mediation will process Usage Data Records as per the source format. · Validate Usage Data Records from each source. · Segregates Usage Data Records coming from each source to multiple, based on the segregation requirement of end Application. · Aggregates Usage Data Records based on the aggregation rule if any from different sources. · Consolidates multiple Usage Data Records from each source. · Delivers formatted Usage Data Records to different end application like Billing, Interconnect, Fraud Management, etc. · Generates audit trail for incoming Usage Data Records and keeps track of all the Usage Data Records at various stages of mediation process. · Checks duplicate Usage Data Records across files for a given time window. 4. Fulfillment This area is responsible for providing customers with their requested products in a timely and correct manner. It translates the customer's business or personal need into a solution that can be delivered using the specific products in the enterprise's portfolio. This process informs the customers of the status of their purchase order, and ensures completion on time, as well as ensuring a delighted customer. These processes are responsible for accepting and issuing orders. They deal with pre-order feasibility determination, credit authorization, order issuance, order status and tracking, customer update on customer order activities, and customer notification on order completion. Order management and provisioning applications fall into this category. The key functionalities provided by these applications are · Issuing new customer orders, modifying open customer orders, or canceling open customer orders; · Verifying whether specific non-standard offerings sought by customers are feasible and supportable; · Checking the credit worthiness of customers as part of the customer order process; · Testing the completed offering to ensure it is working correctly; · Updating of the Customer Inventory Database to reflect that the specific product offering has been allocated, modified, or cancelled; · Assigning and tracking customer provisioning activities; · Managing customer provisioning jeopardy conditions; and · Reporting progress on customer orders and other processes to customer. These applications typically get orders from CRM systems. They interact with network elements and billing systems for fulfillment of orders. 5. Enterprise Management This process area includes those processes that manage enterprise-wide activities and needs, or have application within the enterprise as a whole. They encompass all business management processes that · Are necessary to support the whole of the enterprise, including processes for financial management, legal management, regulatory management, process, cost, and quality management, etc.; · Are responsible for setting corporate policies, strategies, and directions, and for providing guidelines and targets for the whole of the business, including strategy development and planning for areas, such as Enterprise Architecture, that are integral to the direction and development of the business; · Occur throughout the enterprise, including processes for project management, performance assessments, cost assessments, etc. (i) Enterprise Risk Management: Enterprise Risk Management focuses on assuring that risks and threats to the enterprise value and/or reputation are identified, and appropriate controls are in place to minimize or eliminate the identified risks. The identified risks may be physical or logical/virtual. Successful risk management ensures that the enterprise can support its mission critical operations, processes, applications, and communications in the face of serious incidents such as security threats/violations and fraud attempts. Two key areas covered in Risk Management by telecom operators are: · Revenue Assurance: Revenue assurance system will be responsible for identifying revenue loss scenarios across components/systems, and will help in rectifying the problems. The following lists the high-level roles and responsibilities executed by the Revenue Assurance system in the end-to-end solution. o Identify all usage information dropped when networks are being upgraded. o Interconnect bill verification. o Identify where services are routinely provisioned but never billed. o Identify poor sales policies that are intensifying collections problems. o Find leakage where usage is sent to error bucket and never billed for. o Find leakage where field service, CRM, and network build-out are not optimized. · Fraud Management: Involves collecting data from different systems to identify abnormalities in traffic patterns, usage patterns, and subscription patterns to report suspicious activity that might suggest fraudulent usage of resources, resulting in revenue losses to the operator. The key roles and responsibilities of the system component are as follows: o Fraud management system will capture and monitor high usage (over a certain threshold) in terms of duration, value, and number of calls for each subscriber. The threshold for each subscriber is decided by the system and fixed automatically. o Fraud management will be able to detect the unauthorized access to services for certain subscribers. These subscribers may have been provided unauthorized services by employees. The component will raise the alert to the operator the very first time of such illegal calls or calls which are not billed. o The solution will be to have an alarm management system that will deliver alarms to the operator/provider whenever it detects a fraud, thus minimizing fraud by catching it the first time it occurs. o The Fraud Management system will be capable of interfacing with switches, mediation systems, and billing systems (ii) Knowledge Management This process focuses on knowledge management, technology research within the enterprise, and the evaluation of potential technology acquisitions. Key responsibilities of knowledge base management are to · Maintain knowledge base – Creation and updating of knowledge base on ongoing basis. · Search knowledge base – Search of knowledge base on keywords or category browse · Maintain metadata – Management of metadata on knowledge base to ensure effective management and search. · Run report generator. · Provide content – Add content to the knowledge base, e.g., user guides, operational manual, etc. (iii) Document Management It focuses on maintaining a repository of all electronic documents or images of paper documents relevant to the enterprise using a system. (iv) Data Management It manages data as a valuable resource for any enterprise. For telecom enterprises, the typical areas covered are Master Data Management, Data Warehousing, and Business Intelligence. It is also responsible for data governance, security, quality, and database management. Key responsibilities of Data Management are · Using ETL, extract the data from CRM, Billing, web content, ERP, campaign management, financial, network operations, asset management info, customer contact data, customer measures, benchmarks, process data, e.g., process inputs, outputs, and measures, into Enterprise Data Warehouse. · Management of data traceability with source, data related business rules/decisions, data quality, data cleansing data reconciliation, competitors data – storage for all the enterprise data (customer profiles, products, offers, revenues, etc.) · Get online update through night time replication or physical backup process at regular frequency. · Provide the data access to business intelligence and other systems for their analysis, report generation, and use. (v) Business Intelligence It uses the Enterprise Data to provide the various analysis and reports that contain prospects and analytics for customer retention, acquisition of new customers due to the offers, and SLAs. It will generate right and optimized plans – bolt-ons for the customers. The following lists the high-level roles and responsibilities executed by the Business Intelligence system at the Enterprise Level: · It will do Pattern analysis and reports problem. · It will do Data Analysis – Statistical analysis, data profiling, affinity analysis of data, customer segment wise usage patterns on offers, products, service and revenue generation against services and customer segments. · It will do Performance (business, system, and forecast) analysis, churn propensity, response time, and SLAs analysis. · It will support for online and offline analysis, and report drill down capability. · It will collect, store, and report various SLA data. · It will provide the necessary intelligence for marketing and working on campaigns, etc., with cost benefit analysis and predictions. It will advise on customer promotions with additional services based on loyalty and credit history of customer · It will Interface with Enterprise Data Management system for data to run reports and analysis tasks. It will interface with the campaign schedules, based on historical success evidence. (vi) Stakeholder and External Relations Management It manages the enterprise's relationship with stakeholders and outside entities. Stakeholders include shareholders, employee organizations, etc. Outside entities include regulators, local community, and unions. Some of the processes within this grouping are Shareholder Relations, External Affairs, Labor Relations, and Public Relations. (vii) Enterprise Resource Planning It is used to manage internal and external resources, including tangible assets, financial resources, materials, and human resources. Its purpose is to facilitate the flow of information between all business functions inside the boundaries of the enterprise and manage the connections to outside stakeholders. ERP systems consolidate all business operations into a uniform and enterprise wide system environment. The key roles and responsibilities for Enterprise System are given below: · It will handle responsibilities such as core accounting, financial, and management reporting. · It will interface with CRM for capturing customer account and details. · It will interface with billing to capture the billing revenue and other financial data. · It will be responsible for executing the dunning process. Billing will send the required feed to ERP for execution of dunning. · It will interface with the CRM and Billing through batch interfaces. Enterprise management systems are like horizontals in the enterprise and typically interact with all major telecom systems. E.g., an ERP system interacts with CRM, Fulfillment, and Billing systems for different kinds of data exchanges. 6. External Interfaces/Touch Points The typical external parties are customers, suppliers/partners, employees, shareholders, and other stakeholders. External interactions from/to a Service Provider to other parties can be achieved by a variety of mechanisms, including: · Exchange of emails or faxes · Call Centers · Web Portals · Business-to-Business (B2B) automated transactions These applications provide an Internet technology driven interface to external parties to undertake a variety of business functions directly for themselves. These can provide fully or partially automated service to external parties through various touch points. Typical characteristics of these touch points are · Pre-integrated self-service system, including stand-alone web framework or integration front end with a portal engine · Self services layer exposing atomic web services/APIs for reuse by multiple systems across the architectural environment · Portlets driven connectivity exposing data and services interoperability through a portal engine or web application These touch points mostly interact with the CRM systems for requests, inquiries, and responses. 7. Middleware The component will be primarily responsible for integrating the different systems components under a common platform. It should provide a Standards-Based Platform for building Service Oriented Architecture and Composite Applications. The following lists the high-level roles and responsibilities executed by the Middleware component in the end-to-end solution. · As an integration framework, covering to and fro interfaces · Provide a web service framework with service registry. · Support SOA framework with SOA service registry. · Each of the interfaces from / to Middleware to other components would handle data transformation, translation, and mapping of data points. · Receive data from the caller / activate and/or forward the data to the recipient system in XML format. · Use standard XML for data exchange. · Provide the response back to the service/call initiator. · Provide a tracking until the response completion. · Keep a store transitional data against each call/transaction. · Interface through Middleware to get any information that is possible and allowed from the existing systems to enterprise systems; e.g., customer profile and customer history, etc. · Provide the data in a common unified format to the SOA calls across systems, and follow the Enterprise Architecture directive. · Provide an audit trail for all transactions being handled by the component. 8. Network Elements The term Network Element means a facility or equipment used in the provision of a telecommunications service. Such terms also includes features, functions, and capabilities that are provided by means of such facility or equipment, including subscriber numbers, databases, signaling systems, and information sufficient for billing and collection or used in the transmission, routing, or other provision of a telecommunications service. Typical network elements in a GSM network are Home Location Register (HLR), Intelligent Network (IN), Mobile Switching Center (MSC), SMS Center (SMSC), and network elements for other value added services like Push-to-talk (PTT), Ring Back Tone (RBT), etc. Network elements are invoked when subscribers use their telecom devices for any kind of usage. These elements generate usage data and pass it on to downstream systems like mediation and billing system for rating and billing. They also integrate with provisioning systems for order/service fulfillment. 9. 3rd Party Applications 3rd Party systems are applications like content providers, payment gateways, point of sale terminals, and databases/applications maintained by the Government. Depending on applicability and the type of functionality provided by 3rd party applications, the integration with different telecom systems like CRM, provisioning, and billing will be done. 10. Service Delivery Platform A service delivery platform (SDP) provides the architecture for the rapid deployment, provisioning, execution, management, and billing of value added telecom services. SDPs are based on the concept of SOA and layered architecture. They support the delivery of voice, data services, and content in network and device-independent fashion. They allow application developers to aggregate network capabilities, services, and sources of content. SDPs typically contain layers for web services exposure, service application development, and network abstraction. SOA Reference Architecture SOA concept is based on the principle of developing reusable business service and building applications by composing those services, instead of building monolithic applications in silos. It’s about bridging the gap between business and IT through a set of business-aligned IT services, using a set of design principles, patterns, and techniques. In an SOA, resources are made available to participants in a value net, enterprise, line of business (typically spanning multiple applications within an enterprise or across multiple enterprises). It consists of a set of business-aligned IT services that collectively fulfill an organization’s business processes and goals. We can choreograph these services into composite applications and invoke them through standard protocols. SOA, apart from agility and reusability, enables: · The business to specify processes as orchestrations of reusable services · Technology agnostic business design, with technology hidden behind service interface · A contractual-like interaction between business and IT, based on service SLAs · Accountability and governance, better aligned to business services · Applications interconnections untangling by allowing access only through service interfaces, reducing the daunting side effects of change · Reduced pressure to replace legacy and extended lifetime for legacy applications, through encapsulation in services · A Cloud Computing paradigm, using web services technologies, that makes possible service outsourcing on an on-demand, utility-like, pay-per-usage basis The following section represents the Reference Architecture of logical view for the Telecom Solution. The new custom built application needs to align with this logical architecture in the long run to achieve EA benefits. Packaged implementation applications, such as ERP billing applications, need to expose their functions as service providers (as other applications consume) and interact with other applications as service consumers. COT applications need to expose services through wrappers such as adapters to utilize existing resources and at the same time achieve Enterprise Architecture goal and objectives. The following are the various layers for Enterprise level deployment of SOA. This diagram captures the abstract view of Enterprise SOA layers and important components of each layer. Layered architecture means decomposition of services such that most interactions occur between adjacent layers. However, there is no strict rule that top layers should not directly communicate with bottom layers. The diagram below represents the important logical pieces that would result from overall SOA transformation. @font-face { font-family: "Arial"; }@font-face { font-family: "Courier New"; }@font-face { font-family: "Wingdings"; }@font-face { font-family: "Cambria"; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoCaption, li.MsoCaption, div.MsoCaption { margin: 0cm 0cm 10pt; font-size: 9pt; font-family: "Times New Roman"; color: rgb(79, 129, 189); font-weight: bold; }p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast { margin: 0cm 0cm 0.0001pt 36pt; font-size: 12pt; font-family: "Times New Roman"; }div.Section1 { page: Section1; }ol { margin-bottom: 0cm; }ul { margin-bottom: 0cm; } Figure 3. Enterprise SOA Reference Architecture 1. Operational System Layer: This layer consists of all packaged applications like CRM, ERP, custom built applications, COTS based applications like Billing, Revenue Management, Fulfilment, and the Enterprise databases that are essential and contribute directly or indirectly to the Enterprise OSS/BSS Transformation. ERP holds the data of Asset Lifecycle Management, Supply Chain, and Advanced Procurement and Human Capital Management, etc. CRM holds the data related to Order, Sales, and Marketing, Customer Care, Partner Relationship Management, Loyalty, etc. Content Management handles Enterprise Search and Query. Billing application consists of the following components: · Collections Management, Customer Billing Management, Invoices, Real-Time Rating, Discounting, and Applying of Charges · Enterprise databases will hold both the application and service data, whether structured or unstructured. MDM - Master data majorly consists of Customer, Order, Product, and Service Data. 2. Enterprise Component Layer: This layer consists of the Application Services and Common Services that are responsible for realizing the functionality and maintaining the QoS of the exposed services. This layer uses container-based technologies such as application servers to implement the components, workload management, high availability, and load balancing. Application Services: This Service Layer enables application, technology, and database abstraction so that the complex accessing logic is hidden from the other service layers. This is a basic service layer, which exposes application functionalities and data as reusable services. The three types of the Application access services are: · Application Access Service: This Service Layer exposes application level functionalities as a reusable service between BSS to BSS and BSS to OSS integration. This layer is enabled using disparate technology such as Web Service, Integration Servers, and Adaptors, etc. · Data Access Service: This Service Layer exposes application data services as a reusable reference data service. This is done via direct interaction with application data. and provides the federated query. · Network Access Service: This Service Layer exposes provisioning layer as a reusable service from OSS to OSS integration. This integration service emphasizes the need for high performance, stateless process flows, and distributed design. Common Services encompasses management of structured, semi-structured, and unstructured data such as information services, portal services, interaction services, infrastructure services, and security services, etc. 3. Integration Layer: This consists of service infrastructure components like service bus, service gateway for partner integration, service registry, service repository, and BPEL processor. Service bus will carry the service invocation payloads/messages between consumers and providers. The other important functions expected from it are itinerary based routing, distributed caching of routing information, transformations, and all qualities of service for messaging-like reliability, scalability, and availability, etc. Service registry will hold all contracts (wsdl) of services, and it helps developers to locate or discover service during design time or runtime. • BPEL processor would be useful in orchestrating the services to compose a complex business scenario or process. • Workflow and business rules management are also required to support manual triggering of certain activities within business process. based on the rules setup and also the state machine information. Application, data, and service mediation layer typically forms the overall composite application development framework or SOA Framework. 4. Business Process Layer: These are typically the intermediate services layer and represent Shared Business Process Services. At Enterprise Level, these services are from Customer Management, Order Management, Billing, Finance, and Asset Management application domains. 5. Access Layer: This layer consists of portals for Enterprise and provides a single view of Enterprise information management and dashboard services. 6. Channel Layer: This consists of various devices; applications that form part of extended enterprise; browsers through which users access the applications. 7. Client Layer: This designates the different types of users accessing the enterprise applications. The type of user typically would be an important factor in determining the level of access to applications. 8. Vertical pieces like management, monitoring, security, and development cut across all horizontal layers Management and monitoring involves all aspects of SOA-like services, SLAs, and other QoS lifecycle processes for both applications and services surrounding SOA governance. 9. EA Governance, Reference Architecture, Roadmap, Principles, and Best Practices: EA Governance is important in terms of providing the overall direction to SOA implementation within the enterprise. This involves board-level involvement, in addition to business and IT executives. At a high level, this involves managing the SOA projects implementation, managing SOA infrastructure, and controlling the entire effort through all fine-tuned IT processes in accordance with COBIT (Control Objectives for Information Technology). Devising tools and techniques to promote reuse culture, and the SOA way of doing things needs competency centers to be established in addition to training the workforce to take up new roles that are suited to SOA journey. Conclusions Reference Architectures can serve as the basis for disparate architecture efforts throughout the organization, even if they use different tools and technologies. Reference architectures provide best practices and approaches in the independent way a vendor deals with technology and standards. Reference Architectures model the abstract architectural elements for an enterprise independent of the technologies, protocols, and products that are used to implement an SOA. Telecom enterprises today are facing significant business and technology challenges due to growing competition, a multitude of services, and convergence. Adopting architectural best practices could go a long way in meeting these challenges. The use of SOA-based architecture for communication to each of the external systems like Billing, CRM, etc., in OSS/BSS system has made the architecture very loosely coupled, with greater flexibility. Any change in the external systems would be absorbed at the Integration Layer without affecting the rest of the ecosystem. The use of a Business Process Management (BPM) tool makes the management and maintenance of the business processes easy, with better performance in terms of lead time, quality, and cost. Since the Architecture is based on standards, it will lower the cost of deploying and managing OSS/BSS applications over their lifecycles.

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Creating a dynamic proxy generator – Part 1 – Creating the Assembly builder, Module builder and cach

- by SeanMcAlinden

I’ve recently started a project with a few mates to learn the ins and outs of Dependency Injection, AOP and a number of other pretty crucial patterns of development as we’ve all been using these patterns for a while but have relied totally on third part solutions to do the magic. We thought it would be interesting to really get into the details by rolling our own IoC container and hopefully learn a lot on the way, and you never know, we might even create an excellent framework. The open source project is called Rapid IoC and is hosted at http://rapidioc.codeplex.com/ One of the most interesting tasks for me is creating the dynamic proxy generator for enabling Aspect Orientated Programming (AOP). In this series of articles, I’m going to track each step I take for creating the dynamic proxy generator and I’ll try my best to explain what everything means - mainly as I’ll be using Reflection.Emit to emit a fair amount of intermediate language code (IL) to create the proxy types at runtime which can be a little taxing to read. It’s worth noting that building the proxy is without a doubt going to be slightly painful so I imagine there will be plenty of areas I’ll need to change along the way. Anyway lets get started… Part 1 - Creating the Assembly builder, Module builder and caching mechanism Part 1 is going to be a really nice simple start, I’m just going to start by creating the assembly, module and type caches. The reason we need to create caches for the assembly, module and types is simply to save the overhead of recreating proxy types that have already been generated, this will be one of the important steps to ensure that the framework is fast… kind of important as we’re calling the IoC container ‘Rapid’ – will be a little bit embarrassing if we manage to create the slowest framework. The Assembly builder The assembly builder is what is used to create an assembly at runtime, we’re going to have two overloads, one will be for the actual use of the proxy generator, the other will be mainly for testing purposes as it will also save the assembly so we can use Reflector to examine the code that has been created. Here’s the code: DynamicAssemblyBuilder using System; using System.Reflection; using System.Reflection.Emit; namespace Rapid.DynamicProxy.Assembly { /// <summary> /// Class for creating an assembly builder. /// </summary> internal static class DynamicAssemblyBuilder { #region Create /// <summary> /// Creates an assembly builder. /// </summary> /// <param name="assemblyName">Name of the assembly.</param> public static AssemblyBuilder Create(string assemblyName) { AssemblyName name = new AssemblyName(assemblyName); AssemblyBuilder assembly = AppDomain.CurrentDomain.DefineDynamicAssembly( name, AssemblyBuilderAccess.Run); DynamicAssemblyCache.Add(assembly); return assembly; } /// <summary> /// Creates an assembly builder and saves the assembly to the passed in location. /// </summary> /// <param name="assemblyName">Name of the assembly.</param> /// <param name="filePath">The file path.</param> public static AssemblyBuilder Create(string assemblyName, string filePath) { AssemblyName name = new AssemblyName(assemblyName); AssemblyBuilder assembly = AppDomain.CurrentDomain.DefineDynamicAssembly( name, AssemblyBuilderAccess.RunAndSave, filePath); DynamicAssemblyCache.Add(assembly); return assembly; } #endregion } } So hopefully the above class is fairly explanatory, an AssemblyName is created using the passed in string for the actual name of the assembly. An AssemblyBuilder is then constructed with the current AppDomain and depending on the overload used, it is either just run in the current context or it is set up ready for saving. It is then added to the cache. DynamicAssemblyCache using System.Reflection.Emit; using Rapid.DynamicProxy.Exceptions; using Rapid.DynamicProxy.Resources.Exceptions; namespace Rapid.DynamicProxy.Assembly { /// <summary> /// Cache for storing the dynamic assembly builder. /// </summary> internal static class DynamicAssemblyCache { #region Declarations private static object syncRoot = new object(); internal static AssemblyBuilder Cache = null; #endregion #region Adds a dynamic assembly to the cache. /// <summary> /// Adds a dynamic assembly builder to the cache. /// </summary> /// <param name="assemblyBuilder">The assembly builder.</param> public static void Add(AssemblyBuilder assemblyBuilder) { lock (syncRoot) { Cache = assemblyBuilder; } } #endregion #region Gets the cached assembly /// <summary> /// Gets the cached assembly builder. /// </summary> /// <returns></returns> public static AssemblyBuilder Get { get { lock (syncRoot) { if (Cache != null) { return Cache; } } throw new RapidDynamicProxyAssertionException(AssertionResources.NoAssemblyInCache); } } #endregion } } The cache is simply a static property that will store the AssemblyBuilder (I know it’s a little weird that I’ve made it public, this is for testing purposes, I know that’s a bad excuse but hey…) There are two methods for using the cache – Add and Get, these just provide thread safe access to the cache. The Module Builder The module builder is required as the create proxy classes will need to live inside a module within the assembly. Here’s the code: DynamicModuleBuilder using System.Reflection.Emit; using Rapid.DynamicProxy.Assembly; namespace Rapid.DynamicProxy.Module { /// <summary> /// Class for creating a module builder. /// </summary> internal static class DynamicModuleBuilder { /// <summary> /// Creates a module builder using the cached assembly. /// </summary> public static ModuleBuilder Create() { string assemblyName = DynamicAssemblyCache.Get.GetName().Name; ModuleBuilder moduleBuilder = DynamicAssemblyCache.Get.DefineDynamicModule (assemblyName, string.Format("{0}.dll", assemblyName)); DynamicModuleCache.Add(moduleBuilder); return moduleBuilder; } } } As you can see, the module builder is created on the assembly that lives in the DynamicAssemblyCache, the module is given the assembly name and also a string representing the filename if the assembly is to be saved. It is then added to the DynamicModuleCache. DynamicModuleCache using System.Reflection.Emit; using Rapid.DynamicProxy.Exceptions; using Rapid.DynamicProxy.Resources.Exceptions; namespace Rapid.DynamicProxy.Module { /// <summary> /// Class for storing the module builder. /// </summary> internal static class DynamicModuleCache { #region Declarations private static object syncRoot = new object(); internal static ModuleBuilder Cache = null; #endregion #region Add /// <summary> /// Adds a dynamic module builder to the cache. /// </summary> /// <param name="moduleBuilder">The module builder.</param> public static void Add(ModuleBuilder moduleBuilder) { lock (syncRoot) { Cache = moduleBuilder; } } #endregion #region Get /// <summary> /// Gets the cached module builder. /// </summary> /// <returns></returns> public static ModuleBuilder Get { get { lock (syncRoot) { if (Cache != null) { return Cache; } } throw new RapidDynamicProxyAssertionException(AssertionResources.NoModuleInCache); } } #endregion } } The DynamicModuleCache is very similar to the assembly cache, it is simply a statically stored module with thread safe Add and Get methods. The DynamicTypeCache To end off this post, I’m going to create the cache for storing the generated proxy classes. I’ve spent a fair amount of time thinking about the type of collection I should use to store the types and have finally decided that for the time being I’m going to use a generic dictionary. This may change when I can actually performance test the proxy generator but the time being I think it makes good sense in theory, mainly as it pretty much maintains it’s performance with varying numbers of items – almost constant (0)1. Plus I won’t ever need to loop through the items which is not the dictionaries strong point. Here’s the code as it currently stands: DynamicTypeCache using System; using System.Collections.Generic; using System.Security.Cryptography; using System.Text; namespace Rapid.DynamicProxy.Types { /// <summary> /// Cache for storing proxy types. /// </summary> internal static class DynamicTypeCache { #region Declarations static object syncRoot = new object(); public static Dictionary<string, Type> Cache = new Dictionary<string, Type>(); #endregion /// <summary> /// Adds a proxy to the type cache. /// </summary> /// <param name="type">The type.</param> /// <param name="proxy">The proxy.</param> public static void AddProxyForType(Type type, Type proxy) { lock (syncRoot) { Cache.Add(GetHashCode(type.AssemblyQualifiedName), proxy); } } /// <summary> /// Tries the type of the get proxy for. /// </summary> /// <param name="type">The type.</param> /// <returns></returns> public static Type TryGetProxyForType(Type type) { lock (syncRoot) { Type proxyType; Cache.TryGetValue(GetHashCode(type.AssemblyQualifiedName), out proxyType); return proxyType; } } #region Private Methods private static string GetHashCode(string fullName) { SHA1CryptoServiceProvider provider = new SHA1CryptoServiceProvider(); Byte[] buffer = Encoding.UTF8.GetBytes(fullName); Byte[] hash = provider.ComputeHash(buffer, 0, buffer.Length); return Convert.ToBase64String(hash); } #endregion } } As you can see, there are two public methods, one for adding to the cache and one for getting from the cache. Hopefully they should be clear enough, the Get is a TryGet as I do not want the dictionary to throw an exception if a proxy doesn’t exist within the cache. Other than that I’ve decided to create a key using the SHA1CryptoServiceProvider, this may change but my initial though is the SHA1 algorithm is pretty fast to put together using the provider and it is also very unlikely to have any hashing collisions. (there are some maths behind how unlikely this is – here’s the wiki if you’re interested http://en.wikipedia.org/wiki/SHA_hash_functions) Anyway, that’s the end of part 1 – although I haven’t started any of the fun stuff (by fun I mean hairpulling, teeth grating Relfection.Emit style fun), I’ve got the basis of the DynamicProxy in place so all we have to worry about now is creating the types, interceptor classes, method invocation information classes and finally a really nice fluent interface that will abstract all of the hard-core craziness away and leave us with a lightning fast, easy to use AOP framework. Hope you find the series interesting. All of the source code can be viewed and/or downloaded at our codeplex site - http://rapidioc.codeplex.com/ Kind Regards, Sean.

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CodePlex Daily Summary for Thursday, March 01, 2012

CodePlex Daily Summary for Thursday, March 01, 2012Popular ReleasesMetodología General Ajustada - MGA: 01.09.08: Cambios John: Cambios en el MDI: Habilitación del menú e ícono de Imprimir. Deshabilitación de menú Ayuda y opciones de Importar y Exportar del menú Proyectos temporalmente. Integración con código de Crystal Report. Validaciones con Try-Catch al generar los reportes, personalización de los formularios en estilos y botones y validación de selección de tipo de reporte. Creación de instalador con TODOS los cambios y la creación de las carpetas asociadas a los RPT.WatchersNET CKEditor™ Provider for DotNetNuke®: CKEditor Provider 1.14.01: Whats NewAdded New Plugin "Ventrian News Articles Link Selector" to select an Article Link from the News Article Module (This Plugin is not visible by default in your Toolbar, you need to manually add the 'newsarticleslinks' to your toolbarset) http://www.watchersnet.de/Portals/0/screenshots/dnn/CKEditorNewsArticlesLinks.png File-Browser: Added Paging to the Files List. You can define the Page Size in the Options (Default Value: 20) http://www.watchersnet.de/Portals/0/screenshots/dnn/CKEdito...MyRouter (Virtual WiFi Router): MyRouter 1.0 (Beta): A friendlier User Interface. A logger file to catch exceptions so you may send it to use to improve and fix any bugs that may occur. A feedback form because we always love hearing what you guy's think of MyRouter. Check for update menu item for you to stay up to date will the latest changes. Facebook fan page so you may spread the word and share MyRouter with friends and family And Many other exciting features were sure your going to love!WPF Sound Visualization Library: WPF SVL 0.3 (Source, Binaries, Examples, Help): Version 0.3 of WPFSVL. This includes three new controls: an equalizer, a digital clock, and a time editor.Thai Flood Watch: Thai Flood Watch - Source: non commercial use only ** This project supported by Department of Computer Science KhonKaen University Thailand.ZXing.Net: ZXing.Net 0.4.0.0: sync with rev. 2196 of the java version important fix for RGBLuminanceSource generating barcode bitmaps Windows Phone demo client (only tested with emulator, because I don't have a Windows Phone) Barcode generation support for Windows Forms demo client Webcam support for Windows Forms demo clientOrchard Project: Orchard 1.4: Please read our release notes for Orchard 1.4: http://docs.orchardproject.net/Documentation/Orchard-1-4-Release-Notes.NET Assembly Information: Assembly Information 2.1.0.1: - Fixed the issue in which AnyCPU binaries were shown as 32bit - Added support to show the errors in-case if some dlls failed to load.FluentData -Micro ORM with a fluent API that makes it simple to query a database: FluentData version 1.2: New features: - QueryValues method - Added support for automapping to enumerations (both int and string are supported). Fixed 2 reported issues.NetSqlAzMan - .NET SQL Authorization Manager: 3.6.0.15: 3.6.0.15 28-Feb-2012 • Fix: The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication because it is in the Faulted state. Work Item 10435: http://netsqlazman.codeplex.com/workitem/10435 • Fix: Made StorageCache thread safe. Thanks to tangrl. • Fix: Members property of SqlAzManApplicationGroup is not functioning. Thanks to tangrl. Work Item 10267: http://netsqlazman.codeplex.com/workitem/10267 • Fix: Indexer are making database calls. Thanks to t...SCCM Client Actions Tool: Client Actions Tool v1.1: SCCM Client Actions Tool v1.1 is the latest version. It comes with following changes since last version: Added stop button to stop the ongoing process. Added action "Query update status". Added option "saveOnlineComputers" in config.ini to enable saving list of online computers from last session. Default value for "LatestClientVersion" set to SP2 R3 (4.00.6487.2157). Wuauserv service manual startup mode is considered healthy on Windows 7. Errors are now suppressed in checkReleases...Kinect PowerPoint Control: Kinect PowerPoint Control v1.1: Updated for Kinect SDK 1.0.SharpCompress - a fully native C# library for RAR, 7Zip, Zip, Tar, GZip, BZip2: SharpCompress 0.8: API Updates: SOLID Extract Method for Archives (7Zip and RAR). ExtractAllEntries method on Archive classes will extract archives as a streaming file. This can offer better 7Zip extraction performance if any of the entries are solid. The IsSolid method on 7Zip archives will return true if any are solid. Removed IExtractionListener was removed in favor of events. Unit tests show example. Bug fixes: PPMd passes tests plus other fixes (Thanks Pavel) Zip used to always write a Post Descri...Social Network Importer for NodeXL: SocialNetImporter(v.1.3): This new version includes: - Download new networks for Facebook fan pages. - New options for downloading more posts - Bug fixes To use the new graph data provider, do the following: Unzip the Zip file into the "PlugIns" folder that can be found in the NodeXL installation folder (i.e "C:\Program Files\Social Media Research Foundation\NodeXL Excel Template\PlugIns") Open NodeXL template and you can access the new importer from the "Import" menuASP.NET REST Services Framework: Release 1.1 - Standard version: Beginning from v1.1 the REST-services Framework is compatible with ASP.NET Routing model as well with CRUD (Create, Read, Update, and Delete) principle. These two are often important when building REST API functionality within your application. It also includes ability to apply Filters to a class to target all WebRest methods, as well as some performance enhancements. New version includes Metadata Explorer providing ability exploring the existing services that becomes essential as the number ...SQL Live Monitor: SQL Live Monitor 1.31: A quick fix to make it this version work with SQL 2012. Version 2 already has 2012 working, but am still developing the UI in version 2, so this is just an interim fix to allow user to monitor SQL 2012.Content Slider Module for DotNetNuke: 01.02.00: This release has the following updates and new features: Feature: One-Click Enabling of Pager Setting Feature: Cache Sliders for Performance Feature: Configurable Cache Setting Enhancement: Transitions can be Selected Bug: Secure Folder Images not Viewable Bug: Sliders Disappear on Postback Bug: Remote Images Cause Error Bug: Deleted Images Cause Error System Requirements DotNetNuke v06.00.00 or newer .Net Framework v3.5 SP1 or newer SQL Server 2005 or newerImage Resizer for Windows: Image Resizer 3 Preview 3: Here is yet another iteration toward what will eventually become Image Resizer 3. This release is stable. However, I'm calling it a preview since there are still many features I'd still like to add before calling it complete. Updated on February 28 to fix an issue with installing on multi-user machines. As usual, here is my progress report. Done Preview 3 Fix: 3206 3076 3077 5688 Fix: 7420 Fix: 7527 Fix: 7576 7612 Preview 2 6308 6309 Fix: 7339 Fix: 7357 Preview 1 UI...Finestra Virtual Desktops: 2.5.4500: This is a bug fix release for version 2.5. It fixes several things and adds a couple of minor features. See the 2.5 release notes for more information on the major new features in that version. Important - If Finestra crashes on startup for you, you must install the Visual C++ 2010 runtime from http://www.microsoft.com/download/en/details.aspx?id=5555. Fixes a bug with window animations not refreshing the screen on XP and with DWM off Fixes a bug with with crashing on XP due to a bug in t...Media Companion: MC 3.432b Release: General Now remembers window location. Catching a few more exceptions when an image is blank TV A couple of UI tweaks Movies Fixed the actor name displaying HTML Fixed crash when using Save files as "movie.nfo", "movie.tbn", & "fanart.jpg" New CSV template for HTML output function Added <createdate> tag for HTML output A couple of UI tweaks Known Issues Multiepisodes are not handled correctly in MC. The created nfo is valid, but they are not displayed in MC correctly & saving the...New Projectsabac: abac cn websiteAION Launcher: simple aion launcher...just edit the background image of your choosing inside the code and other things such as the links for the buttons and the ip adress and port of the serverAXTFSTool: Dynamics AX tool that connects to your project's TFS and lists the objects your colleagues have changed. Written in C#, still under development and improvements. Useful for team leaders, deployment managers, etc.cookieTopo: Topo map viewerCrmFetchKit.js: Simple Library at allows the execution of fetchxml queries via JavaScript for Dynamics CRM 2011 (using the new WCF endpoints). Like the CrmRestKit this framework uses the promise/A capacities of jQuery. The code and the idea for this framework bases on the CrmServiceToolkit (http://crmtoolkit.codeplex.com/) developed by Daniel Cai. cy univerX engine: ????????DNSAPI.NET: A common API for managing DNS servers on Windows. This project is based on the work I started back in 2002 when I needed to create a web front-end for Windows' DNS server using the .Net framework. The plan is to expand on the project and include support for the BIND server on Windows too. ego.net: ego.netfdTFS: Team Foundation Server Source Control Plugin for FlashDevelopGeoWPS: GeoWPS is an implementation of the OGC WPS. It will be developed in C#. IThink: A new project.King Garden: Boy King's .net practical projects.King Garret: Boy King's .net learning projects.LottoCheck: Follow LottoNot-Terraria: This is a like terraria game but NOT terrariaPassword Protector: Password Protector SharePoint 2010 BlobCache Manager: Manage your web application's blobcache settings directly in the central administration.SharePoint 2010 SilverLight Multiple File Uploader: SharePoint 2010 SilverLight Multiple File Uploader for Documents Libraries with MetaData.Sharepoint Tool Collection: I want to Integrate Various Utilities of Sharepoint at one place. It is for easy working of user or developer. Ex-1. A utility which takes some params & csv file and upload 100s of items on the sharepoint list easily. Ex-2 A utility to upload documents in a library. etc.SQLCLR Cmd Exec Framework Example: For users of MS SQL Server, xp_cmdshell is a utility that we usually want to have disabled. However there are still cases where calling a command line is needed. This project provides an framework/example to make command line calls. It is not meant as an xp_cmdshell replacement but as a workaround.Symmetric Designs Python 3.2: Symmetric Designs for Python 3.2 helps graphical artists to design and develop their own designs freestyle. It uses the pygame module for Python 3.2. It can also be analysed in order to get a grasp of graphics programming in Python.Terminsoft open CLR libraries: Terminsoft open CLR libraries. The first is Terminsoft.Intervals, intended for modeling the sets of intervals with elements, the comparison operation is defined for. The second is Terminsoft.Syntax, intended for text parsing and transformation and built upon regular expressions.Thai Flood Watch: Thai Flood Watch provides useful information, up-to-date and visual access to the major canal in Bangkok, Thailand using data from department of drainage and sewerage. Easily monitor river and canal flow information in Bangkok area, right from your hand.TheNerd: Sample video game source code. Using Sunburn.Unity.WebAPI: A library that allows simple Integration of Microsoft's Unity IoC container with ASP.NET's WebAPI. This project includes a bespoke DependencyResolver that creates a child container per HTTP request and disposes of all registered IDisposable instances at the end of the request.Wholemy.RemoteTouch: The project is a remote touch-sensitive keyboard with a customizable interface which allows to supplement control of another computer, regardless of the wires. For example, if you have not so fast Tablet PC - a client and a fast desktop computer - the server using the network.WindowPlace: WindowPlace makes it possible to save Window positions and sizes to a profile. Switching between profiles will effortlessly move and resize your windows. Help improve productivity - especially for multi-monitor systems. Developed in C# using WPF and a few Windows API calls in the background. WP Error Manager (Devv.Core.WPErrorManager): Library to log, handle and report errors on Windows Phone 7 apps. Fully customizable and extremely easy to implement. Works with any WP7 app. Tested with the emulator, Nokia Lumia 800 and Samsung Focus Flash.WPMatic: Windows Phone7 App to manage Homematic (eQ-3) Devices. The App is like the Homematic Central Configuration Unit (CCU) in German.www.Nabaza.com Freeware and Ebooks: www.Nabaza.com Freeware and Ebooks by William R. NabazaZap: Zap is a light weight .NET communication framework. It is designed for programs running in local area network. Zap provides code generation tool that enables user to call remote methods, add/remote event listener to remote objects, while hides the lower details.

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A Taxonomy of Numerical Methods v1

- by JoshReuben

Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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Pure Server-Side Filtering with RadGridView and WCF RIA Services

Those of you who are familiar with WCF RIA Services know that the DomainDataSource control provides a FilterDescriptors collection that enables you to filter data returned by the query on the server. We have been using this DomainDataSource feature in our RIA Services with DomainDataSource online example for almost an year now. In the example, we are listening for RadGridViews Filtering event in order to intercept any filtering that is performed on the client and translate it to something that the DomainDataSource will understand, in this case a System.Windows.Data.FilterDescriptor being added or removed from its FilterDescriptors collection. Think of RadGridView.FilterDescriptors as client-side filtering and of DomainDataSource.FilterDescriptors as server-side filtering. We no longer need the client-side one. With the introduction of the Custom Filtering Controls feature many new possibilities have opened. With these custom controls we no longer need to do any filtering on the client. I have prepared a very small project that demonstrates how to filter solely on the server by using a custom filtering control. As I have already mentioned filtering on the server is done through the FilterDescriptors collection of the DomainDataSource control. This collection holds instances of type System.Windows.Data.FilterDescriptor. The FilterDescriptor has three important properties: PropertyPath: Specifies the name of the property that we want to filter on (the left operand). Operator: Specifies the type of comparison to use when filtering. An instance of FilterOperator Enumeration. Value: The value to compare with (the right operand). An instance of the Parameter Class. By adding filters, you can specify that only entities which meet the condition in the filter are loaded from the domain context. In case you are not familiar with these concepts you might find Brad Abrams blog interesting. Now, our requirements are to create some kind of UI that will manipulate the DomainDataSource.FilterDescriptors collection. When it comes to collections, my first choice of course would be RadGridView. If you are not familiar with the Custom Filtering Controls concept I would strongly recommend getting acquainted with my step-by-step tutorial Custom Filtering with RadGridView for Silverlight and checking the online example out. I have created a simple custom filtering control that contains a RadGridView and several buttons. This control is aware of the DomainDataSource instance, since it is operating on its FilterDescriptors collection. In fact, the RadGridView that is inside it is bound to this collection. In order to display filters that are relevant for the current column only, I have applied a filter to the grid. This filter is a Telerik.Windows.Data.FilterDescriptor and is used to filter the little grid inside the custom control. It should not be confused with the DomainDataSource.FilterDescriptors collection that RadGridView is actually bound to. These are the RIA filters. Additionally, I have added several other features. For example, if you have specified a DataFormatString on your original column, the Value column inside the custom control will pick it up and format the filter values accordingly. Also, I have transferred the data type of the column that you are filtering to the Value column of the custom control. This will help the little RadGridView determine what kind of editor to show up when you begin edit, for example a date picker for DateTime columns. Finally, I have added four buttons two of them can be used to add or remove filters and the other two will communicate the changes you have made to the server. Here is the full source code of the DomainDataSourceFilteringControl. The XAML: <UserControl x:Class="PureServerSideFiltering.DomainDataSourceFilteringControl" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:telerikGrid="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.GridView" xmlns:telerik="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls" Width="300"> <Border x:Name="LayoutRoot" BorderThickness="1" BorderBrush="#FF8A929E" Padding="5" Background="#FFDFE2E5"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="150"/> <RowDefinition Height="Auto"/> </Grid.RowDefinitions> <StackPanel Grid.Row="0" Margin="2" Orientation="Horizontal" HorizontalAlignment="Center"> <telerik:RadButton Name="addFilterButton" Click="OnAddFilterButtonClick" Content="Add Filter" Margin="2" Width="96"/> <telerik:RadButton Name="removeFilterButton" Click="OnRemoveFilterButtonClick" Content="Remove Filter" Margin="2" Width="96"/> </StackPanel> <telerikGrid:RadGridView Name="filtersGrid" Grid.Row="1" Margin="2" ItemsSource="{Binding FilterDescriptors}" AddingNewDataItem="OnFilterGridAddingNewDataItem" ColumnWidth="*" ShowGroupPanel="False" AutoGenerateColumns="False" CanUserResizeColumns="False" CanUserReorderColumns="False" CanUserFreezeColumns="False" RowIndicatorVisibility="Collapsed" IsFilteringAllowed="False" CanUserSortColumns="False"> <telerikGrid:RadGridView.Columns> <telerikGrid:GridViewComboBoxColumn DataMemberBinding="{Binding Operator}" UniqueName="Operator"/> <telerikGrid:GridViewDataColumn Header="Value" DataMemberBinding="{Binding Value.Value}" UniqueName="Value"/> </telerikGrid:RadGridView.Columns> </telerikGrid:RadGridView> <StackPanel Grid.Row="2" Margin="2" Orientation="Horizontal" HorizontalAlignment="Center"> <telerik:RadButton Name="filterButton" Click="OnApplyFiltersButtonClick" Content="Apply Filters" Margin="2" Width="96"/> <telerik:RadButton Name="clearButton" Click="OnClearFiltersButtonClick" Content="Clear Filters" Margin="2" Width="96"/> </StackPanel> </Grid> </Border> </UserControl> And the code-behind: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Windows; using System.Windows.Controls; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Animation; using System.Windows.Shapes; using Telerik.Windows.Controls.GridView; using System.Windows.Data; using Telerik.Windows.Controls; using Telerik.Windows.Data; namespace PureServerSideFiltering { /// <summary> /// A custom filtering control capable of filtering purely server-side. /// </summary> public partial class DomainDataSourceFilteringControl : UserControl, IFilteringControl { // The main player here. DomainDataSource domainDataSource; // This is the name of the property that this column displays. private string dataMemberName; // This is the type of the property that this column displays. private Type dataMemberType; /// <summary> /// Identifies the <see cref="IsActive"/> dependency property. /// </summary> /// <remarks> /// The state of the filtering funnel (i.e. full or empty) is bound to this property. /// </remarks> public static readonly DependencyProperty IsActiveProperty = DependencyProperty.Register( "IsActive", typeof(bool), typeof(DomainDataSourceFilteringControl), new PropertyMetadata(false)); /// <summary> /// Gets or sets a value indicating whether the filtering is active. /// </summary> /// <remarks> /// Set this to true if you want to lit-up the filtering funnel. /// </remarks> public bool IsActive { get { return (bool)GetValue(IsActiveProperty); } set { SetValue(IsActiveProperty, value); } } /// <summary> /// Gets or sets the domain data source. /// We need this in order to work on its FilterDescriptors collection. /// </summary> /// <value>The domain data source.</value> public DomainDataSource DomainDataSource { get { return this.domainDataSource; } set { this.domainDataSource = value; } } public System.Windows.Data.FilterDescriptorCollection FilterDescriptors { get { return this.DomainDataSource.FilterDescriptors; } } public DomainDataSourceFilteringControl() { InitializeComponent(); } public void Prepare(GridViewBoundColumnBase column) { this.LayoutRoot.DataContext = this; if (this.DomainDataSource == null) { // Sorry, but we need a DomainDataSource. Can't do anything without it. return; } // This is the name of the property that this column displays. this.dataMemberName = column.GetDataMemberName(); // This is the type of the property that this column displays. // We need this in order to see which FilterOperators to feed to the combo-box column. this.dataMemberType = column.DataType; // We will use our magic Type extension method to see which operators are applicable for // this data type. You can go to the extension method body and see what it does. ((GridViewComboBoxColumn)this.filtersGrid.Columns["Operator"]).ItemsSource = this.dataMemberType.ApplicableFilterOperators(); // This is very nice as well. We will tell the Value column its data type. In this way // RadGridView will pick up the best editor according to the data type. For example, // if the data type of the value is DateTime, you will be editing it with a DatePicker. // Nice! ((GridViewDataColumn)this.filtersGrid.Columns["Value"]).DataType = this.dataMemberType; // Yet another nice feature. We will transfer the original DataFormatString (if any) to // the Value column. In this way if you have specified a DataFormatString for the original // column, you will see all filter values formatted accordingly. ((GridViewDataColumn)this.filtersGrid.Columns["Value"]).DataFormatString = column.DataFormatString; // This is important. Since our little filtersGrid will be bound to the entire collection // of this.domainDataSource.FilterDescriptors, we need to set a Telerik filter on the // grid so that it will display FilterDescriptor which are relevane to this column ONLY! Telerik.Windows.Data.FilterDescriptor columnFilter = new Telerik.Windows.Data.FilterDescriptor("PropertyPath" , Telerik.Windows.Data.FilterOperator.IsEqualTo , this.dataMemberName); this.filtersGrid.FilterDescriptors.Add(columnFilter); // We want to listen for this in order to activate and de-activate the UI funnel. this.filtersGrid.Items.CollectionChanged += this.OnFilterGridItemsCollectionChanged; } /// <summary> // Since the DomainDataSource is a little bit picky about adding uninitialized FilterDescriptors // to its collection, we will prepare each new instance with some default values and then // the user can change them later. Go to the event handler to see how we do this. /// </summary> void OnFilterGridAddingNewDataItem(object sender, GridViewAddingNewEventArgs e) { // We need to initialize the new instance with some values and let the user go on from here. System.Windows.Data.FilterDescriptor newFilter = new System.Windows.Data.FilterDescriptor(); // This is a must. It should know what member it is filtering on. newFilter.PropertyPath = this.dataMemberName; // Initialize it with one of the allowed operators. // TypeExtensions.ApplicableFilterOperators method for more info. newFilter.Operator = this.dataMemberType.ApplicableFilterOperators().First(); if (this.dataMemberType == typeof(DateTime)) { newFilter.Value.Value = DateTime.Now; } else if (this.dataMemberType == typeof(string)) { newFilter.Value.Value = "<enter text>"; } else if (this.dataMemberType.IsValueType) { // We need something non-null for all value types. newFilter.Value.Value = Activator.CreateInstance(this.dataMemberType); } // Let the user edit the new filter any way he/she likes. e.NewObject = newFilter; } void OnFilterGridItemsCollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) { // We are active only if we have any filters define. In this case the filtering funnel will lit-up. this.IsActive = this.filtersGrid.Items.Count > 0; } private void OnApplyFiltersButtonClick(object sender, RoutedEventArgs e) { if (this.DomainDataSource.IsLoadingData) { return; } // Comment this if you want the popup to stay open after the button is clicked. this.ClosePopup(); // Since this.domainDataSource.AutoLoad is false, this will take into // account all filtering changes that the user has made since the last // Load() and pull the new data to the client. this.DomainDataSource.Load(); } private void OnClearFiltersButtonClick(object sender, RoutedEventArgs e) { if (this.DomainDataSource.IsLoadingData) { return; } // We want to remove ONLY those filters from the DomainDataSource // that this control is responsible for. this.DomainDataSource.FilterDescriptors .Where(fd => fd.PropertyPath == this.dataMemberName) // Only "our" filters. .ToList() .ForEach(fd => this.DomainDataSource.FilterDescriptors.Remove(fd)); // Bye-bye! // Comment this if you want the popup to stay open after the button is clicked. this.ClosePopup(); // After we did our housekeeping, get the new data to the client. this.DomainDataSource.Load(); } private void OnAddFilterButtonClick(object sender, RoutedEventArgs e) { if (this.DomainDataSource.IsLoadingData) { return; } // Let the user enter his/or her requirements for a new filter. this.filtersGrid.BeginInsert(); this.filtersGrid.UpdateLayout(); } private void OnRemoveFilterButtonClick(object sender, RoutedEventArgs e) { if (this.DomainDataSource.IsLoadingData) { return; } // Find the currently selected filter and destroy it. System.Windows.Data.FilterDescriptor filterToRemove = this.filtersGrid.SelectedItem as System.Windows.Data.FilterDescriptor; if (filterToRemove != null && this.DomainDataSource.FilterDescriptors.Contains(filterToRemove)) { this.DomainDataSource.FilterDescriptors.Remove(filterToRemove); } } private void ClosePopup() { System.Windows.Controls.Primitives.Popup popup = this.ParentOfType<System.Windows.Controls.Primitives.Popup>(); if (popup != null) { popup.IsOpen = false; } } } } Finally, we need to tell RadGridViews Columns to use this custom control instead of the default one. Here is how to do it: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Windows; using System.Windows.Controls; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Animation; using System.Windows.Shapes; using System.Windows.Data; using Telerik.Windows.Data; using Telerik.Windows.Controls; using Telerik.Windows.Controls.GridView; namespace PureServerSideFiltering { public partial class MainPage : UserControl { public MainPage() { InitializeComponent(); this.grid.AutoGeneratingColumn += this.OnGridAutoGeneratingColumn; // Uncomment this if you want the DomainDataSource to start pre-filtered. // You will notice how our custom filtering controls will correctly read this information, // populate their UI with the respective filters and lit-up the funnel to indicate that // filtering is active. Go ahead and try it. this.employeesDataSource.FilterDescriptors.Add(new System.Windows.Data.FilterDescriptor("Title", System.Windows.Data.FilterOperator.Contains, "Assistant")); this.employeesDataSource.FilterDescriptors.Add(new System.Windows.Data.FilterDescriptor("HireDate", System.Windows.Data.FilterOperator.IsGreaterThan, new DateTime(1998, 12, 31))); this.employeesDataSource.FilterDescriptors.Add(new System.Windows.Data.FilterDescriptor("HireDate", System.Windows.Data.FilterOperator.IsLessThanOrEqualTo, new DateTime(1999, 12, 31))); this.employeesDataSource.Load(); } /// <summary> /// First of all, we will need to replace the default filtering control /// of each column with out custom filtering control DomainDataSourceFilteringControl /// </summary> private void OnGridAutoGeneratingColumn(object sender, GridViewAutoGeneratingColumnEventArgs e) { GridViewBoundColumnBase dataColumn = e.Column as GridViewBoundColumnBase; if (dataColumn != null) { // We do not like ugly dates. if (dataColumn.DataType == typeof(DateTime)) { dataColumn.DataFormatString = "{0:d}"; // Short date pattern. // Notice how this format will be later transferred to the Value column // of the grid that we have inside the DomainDataSourceFilteringControl. } // Replace the default filtering control with our. dataColumn.FilteringControl = new DomainDataSourceFilteringControl() { // Let the control know about the DDS, after all it will work directly on it. DomainDataSource = this.employeesDataSource }; // Finally, lit-up the filtering funnel through the IsActive dependency property // in case there are some filters on the DDS that match our column member. string dataMemberName = dataColumn.GetDataMemberName(); dataColumn.FilteringControl.IsActive = this.employeesDataSource.FilterDescriptors .Where(fd => fd.PropertyPath == dataMemberName) .Count() > 0; } } } } The best part is that we are not only writing filters for the DomainDataSource we can read and load them. If the DomainDataSource has some pre-existing filters (like I have created in the code above), our control will read them and will populate its UI accordingly. Even the filtering funnel will light-up! Remember, the funnel is controlled by the IsActive property of our control. While this is just a basic implementation, the source code is absolutely yours and you can take it from here and extend it to match your specific business requirements. Below the main grid there is another debug grid. With its help you can monitor what filter descriptors are added and removed to the domain data source. Download Source Code. (You will have to have the AdventureWorks sample database installed on the default SQLExpress instance in order to run it.) Enjoy!Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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Announcing the release of the Windows Azure SDK 2.1 for .NET

- by ScottGu

Today we released the v2.1 update of the Windows Azure SDK for .NET. This is a major refresh of the Windows Azure SDK and it includes some great new features and enhancements. These new capabilities include: Visual Studio 2013 Preview Support: The Windows Azure SDK now supports using the new VS 2013 Preview Visual Studio 2013 VM Image: Windows Azure now has a built-in VM image that you can use to host and develop with VS 2013 in the cloud Visual Studio Server Explorer Enhancements: Redesigned with improved filtering and auto-loading of subscription resources Virtual Machines: Start and Stop VM’s w/suspend billing directly from within Visual Studio Cloud Services: New Emulator Express option with reduced footprint and Run as Normal User support Service Bus: New high availability options, Notification Hub support, Improved VS tooling PowerShell Automation: Lots of new PowerShell commands for automating Web Sites, Cloud Services, VMs and more All of these SDK enhancements are now available to start using immediately and you can download the SDK from the Windows Azure .NET Developer Center. Visual Studio’s Team Foundation Service (http://tfs.visualstudio.com/) has also been updated to support today’s SDK 2.1 release, and the SDK 2.1 features can now be used with it (including with automated builds + tests). Below are more details on the new features and capabilities released today: Visual Studio 2013 Preview Support Today’s Window Azure SDK 2.1 release adds support for the recent Visual Studio 2013 Preview. The 2.1 SDK also works with Visual Studio 2010 and Visual Studio 2012, and works side by side with the previous Windows Azure SDK 1.8 and 2.0 releases. To install the Windows Azure SDK 2.1 on your local computer, choose the “install the sdk” link from the Windows Azure .NET Developer Center. Then, chose which version of Visual Studio you want to use it with. Clicking the third link will install the SDK with the latest VS 2013 Preview: If you don’t already have the Visual Studio 2013 Preview installed on your machine, this will also install Visual Studio Express 2013 Preview for Web. Visual Studio 2013 VM Image Hosted in the Cloud One of the requests we’ve heard from several customers has been to have the ability to host Visual Studio within the cloud (avoiding the need to install anything locally on your computer). With today’s SDK update we’ve added a new VM image to the Windows Azure VM Gallery that has Visual Studio Ultimate 2013 Preview, SharePoint 2013, SQL Server 2012 Express and the Windows Azure 2.1 SDK already installed on it. This provides a really easy way to create a development environment in the cloud with the latest tools. With the recent shutdown and suspend billing feature we shipped on Windows Azure last month, you can spin up the image only when you want to do active development, and then shut down the virtual machine and not have to worry about usage charges while the virtual machine is not in use. You can create your own VS image in the cloud by using the New->Compute->Virtual Machine->From Gallery menu within the Windows Azure Management Portal, and then by selecting the “Visual Studio Ultimate 2013 Preview” template: Visual Studio Server Explorer: Improved Filtering/Management of Subscription Resources With the Windows Azure SDK 2.1 release you’ll notice significant improvements in the Visual Studio Server Explorer. The explorer has been redesigned so that all Windows Azure services are now contained under a single Windows Azure node. From the top level node you can now manage your Windows Azure credentials, import a subscription file or filter Server Explorer to only show services from particular subscriptions or regions. Note: The Web Sites and Mobile Services nodes will appear outside the Windows Azure Node until the final release of VS 2013. If you have installed the ASP.NET and Web Tools Preview Refresh, though, the Web Sites node will appear inside the Windows Azure node even with the VS 2013 Preview. Once your subscription information is added, Windows Azure services from all your subscriptions are automatically enumerated in the Server Explorer. You no longer need to manually add services to Server Explorer individually. This provides a convenient way of viewing all of your cloud services, storage accounts, service bus namespaces, virtual machines, and web sites from one location: Subscription and Region Filtering Support Using the Windows Azure node in Server Explorer, you can also now filter your Windows Azure services in the Server Explorer by the subscription or region they are in. If you have multiple subscriptions but need to focus your attention to just a few subscription for some period of time, this a handy way to hide the services from other subscriptions view until they become relevant. You can do the same sort of filtering by region. To enable this, just select “Filter Services” from the context menu on the Windows Azure node: Then choose the subscriptions and/or regions you want to filter by. In the below example, I’ve decided to show services from my pay-as-you-go subscription within the East US region: Visual Studio will then automatically filter the items that show up in the Server Explorer appropriately: With storage accounts and service bus namespaces, you sometimes need to work with services outside your subscription. To accommodate that scenario, those services allow you to attach an external account (from the context menu). You’ll notice that external accounts have a slightly different icon in server explorer to indicate they are from outside your subscription. Other Improvements We’ve also improved the Server Explorer by adding additional properties and actions to the service exposed. You now have access to most of the properties on a cloud service, deployment slot, role or role instance as well as the properties on storage accounts, virtual machines and web sites. Just select the object of interest in Server Explorer and view the properties in the property pane. We also now have full support for creating/deleting/update storage tables, blobs and queues from directly within Server Explorer. Simply right-click on the appropriate storage account node and you can create them directly within Visual Studio: Virtual Machines: Start/Stop within Visual Studio Virtual Machines now have context menu actions that allow you start, shutdown, restart and delete a Virtual Machine directly within the Visual Studio Server Explorer. The shutdown action enables you to shut down the virtual machine and suspend billing when the VM is not is use, and easily restart it when you need it: This is especially useful in Dev/Test scenarios where you can start a VM – such as a SQL Server – during your development session and then shut it down / suspend billing when you are not developing (and no longer be billed for it). You can also now directly remote desktop into VMs using the “Connect using Remote Desktop” context menu command in VS Server Explorer. Cloud Services: Emulator Express with Run as Normal User Support You can now launch Visual Studio and run your cloud services locally as a Normal User (without having to elevate to an administrator account) using a new Emulator Express option included as a preview feature with this SDK release. Emulator Express is a version of the Windows Azure Compute Emulator that runs a restricted mode – one instance per role – and it doesn’t require administrative permissions and uses 40% less resources than the full Windows Azure Emulator. Emulator Express supports both web and worker roles. To run your application locally using the Emulator Express option, simply change the following settings in the Windows Azure project. On the shortcut menu for the Windows Azure project, choose Properties, and then choose the Web tab. Check the setting for IIS (Internet Information Services). Make sure that the option is set to IIS Express, not the full version of IIS. Emulator Express is not compatible with full IIS. On the Web tab, choose the option for Emulator Express. Service Bus: Notification Hubs With the Windows Azure SDK 2.1 release we are adding support for Windows Azure Notification Hubs as part of our official Windows Azure SDK, inside of Microsoft.ServiceBus.dll (previously the Notification Hub functionality was in a preview assembly). You are now able to create, update and delete Notification Hubs programmatically, manage your device registrations, and send push notifications to all your mobile clients across all platforms (Windows Store, Windows Phone 8, iOS, and Android). Learn more about Notification Hubs on MSDN here, or watch the Notification Hubs //BUILD/ presentation here. Service Bus: Paired Namespaces One of the new features included with today’s Windows Azure SDK 2.1 release is support for Service Bus “Paired Namespaces”. Paired Namespaces enable you to better handle situations where a Service Bus service namespace becomes unavailable (for example: due to connectivity issues or an outage) and you are unable to send or receive messages to the namespace hosting the queue, topic, or subscription. Previously,to handle this scenario you had to manually setup separate namespaces that can act as a backup, then implement manual failover and retry logic which was sometimes tricky to get right. Service Bus now supports Paired Namespaces, which enables you to connect two namespaces together. When you activate the secondary namespace, messages are stored in the secondary queue for delivery to the primary queue at a later time. If the primary container (namespace) becomes unavailable for some reason, automatic failover enables the messages in the secondary queue. For detailed information about paired namespaces and high availability, see the new topic Asynchronous Messaging Patterns and High Availability. Service Bus: Tooling Improvements In this release, the Windows Azure Tools for Visual Studio contain several enhancements and changes to the management of Service Bus messaging entities using Visual Studio’s Server Explorer. The most noticeable change is that the Service Bus node is now integrated into the Windows Azure node, and supports integrated subscription management. Additionally, there has been a change to the code generated by the Windows Azure Worker Role with Service Bus Queue project template. This code now uses an event-driven “message pump” programming model using the QueueClient.OnMessage method. PowerShell: Tons of New Automation Commands Since my last blog post on the previous Windows Azure SDK 2.0 release, we’ve updated Windows Azure PowerShell (which is a separate download) five times. You can find the full change log here. We’ve added new cmdlets in the following areas: China instance and Windows Azure Pack support Environment Configuration VMs Cloud Services Web Sites Storage SQL Azure Service Bus China Instance and Windows Azure Pack We now support the following cmdlets for the China instance and Windows Azure Pack, respectively: China Instance: Web Sites, Service Bus, Storage, Cloud Service, VMs, Network Windows Azure Pack: Web Sites, Service Bus We will have full cmdlet support for these two Windows Azure environments in PowerShell in the near future. Virtual Machines: Stop/Start Virtual Machines Similar to the Start/Stop VM capability in VS Server Explorer, you can now stop your VM and suspend billing: If you want to keep the original behavior of keeping your stopped VM provisioned, you can pass in the -StayProvisioned switch parameter. Virtual Machines: VM endpoint ACLs We’ve added and updated a bunch of cmdlets for you to configure fine-grained network ACL on your VM endpoints. You can use the following cmdlets to create ACL config and apply them to a VM endpoint: New-AzureAclConfig Get-AzureAclConfig Set-AzureAclConfig Remove-AzureAclConfig Add-AzureEndpoint -ACL Set-AzureEndpoint –ACL The following example shows how to add an ACL rule to an existing endpoint of a VM. Other improvements for Virtual Machine management includes Added -NoWinRMEndpoint parameter to New-AzureQuickVM and Add-AzureProvisioningConfig to disable Windows Remote Management Added -DirectServerReturn parameter to Add-AzureEndpoint and Set-AzureEndpoint to enable/disable direct server return Added Set-AzureLoadBalancedEndpoint cmdlet to modify load balanced endpoints Cloud Services: Remote Desktop and Diagnostics Remote Desktop and Diagnostics are popular debugging options for Cloud Services. We’ve introduced cmdlets to help you configure these two Cloud Service extensions from Windows Azure PowerShell. Windows Azure Cloud Services Remote Desktop extension: New-AzureServiceRemoteDesktopExtensionConfig Get-AzureServiceRemoteDesktopExtension Set-AzureServiceRemoteDesktopExtension Remove-AzureServiceRemoteDesktopExtension Windows Azure Cloud Services Diagnostics extension New-AzureServiceDiagnosticsExtensionConfig Get-AzureServiceDiagnosticsExtension Set-AzureServiceDiagnosticsExtension Remove-AzureServiceDiagnosticsExtension The following example shows how to enable Remote Desktop for a Cloud Service. Web Sites: Diagnostics With our last SDK update, we introduced the Get-AzureWebsiteLog –Tail cmdlet to get the log streaming of your Web Sites. Recently, we’ve also added cmdlets to configure Web Site application diagnostics: Enable-AzureWebsiteApplicationDiagnostic Disable-AzureWebsiteApplicationDiagnostic The following 2 examples show how to enable application diagnostics to the file system and a Windows Azure Storage Table: SQL Database Previously, you had to know the SQL Database server admin username and password if you want to manage the database in that SQL Database server. Recently, we’ve made the experience much easier by not requiring the admin credential if the database server is in your subscription. So you can simply specify the -ServerName parameter to tell Windows Azure PowerShell which server you want to use for the following cmdlets. Get-AzureSqlDatabase New-AzureSqlDatabase Remove-AzureSqlDatabase Set-AzureSqlDatabase We’ve also added a -AllowAllAzureServices parameter to New-AzureSqlDatabaseServerFirewallRule so that you can easily add a firewall rule to whitelist all Windows Azure IP addresses. Besides the above experience improvements, we’ve also added cmdlets get the database server quota and set the database service objective. Check out the following cmdlets for details. Get-AzureSqlDatabaseServerQuota Get-AzureSqlDatabaseServiceObjective Set-AzureSqlDatabase –ServiceObjective Storage and Service Bus Other new cmdlets include Storage: CRUD cmdlets for Azure Tables and Queues Service Bus: Cmdlets for managing authorization rules on your Service Bus Namespace, Queue, Topic, Relay and NotificationHub Summary Today’s release includes a bunch of great features that enable you to build even better cloud solutions. All the above features/enhancements are shipped and available to use immediately as part of the 2.1 release of the Windows Azure SDK for .NET. If you don’t already have a Windows Azure account, you can sign-up for a free trial and start using all of the above features today. Then visit the Windows Azure Developer Center to learn more about how to build apps with it. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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When is a SQL function not a function?

- by Rob Farley

Should SQL Server even have functions? (Oh yeah – this is a T-SQL Tuesday post, hosted this month by Brad Schulz) Functions serve an important part of programming, in almost any language. A function is a piece of code that is designed to return something, as opposed to a piece of code which isn’t designed to return anything (which is known as a procedure). SQL Server is no different. You can call stored procedures, even from within other stored procedures, and you can call functions and use these in other queries. Stored procedures might query something, and therefore ‘return data’, but a function in SQL is considered to have the type of the thing returned, and can be used accordingly in queries. Consider the internal GETDATE() function. SELECT GETDATE(), SomeDatetimeColumn FROM dbo.SomeTable; There’s no logical difference between the field that is being returned by the function and the field that’s being returned by the table column. Both are the datetime field – if you didn’t have inside knowledge, you wouldn’t necessarily be able to tell which was which. And so as developers, we find ourselves wanting to create functions that return all kinds of things – functions which look up values based on codes, functions which do string manipulation, and so on. But it’s rubbish. Ok, it’s not all rubbish, but it mostly is. And this isn’t even considering the SARGability impact. It’s far more significant than that. (When I say the SARGability aspect, I mean “because you’re unlikely to have an index on the result of some function that’s applied to a column, so try to invert the function and query the column in an unchanged manner”) I’m going to consider the three main types of user-defined functions in SQL Server: Scalar Inline Table-Valued Multi-statement Table-Valued I could also look at user-defined CLR functions, including aggregate functions, but not today. I figure that most people don’t tend to get around to doing CLR functions, and I’m going to focus on the T-SQL-based user-defined functions. Most people split these types of function up into two types. So do I. Except that most people pick them based on ‘scalar or table-valued’. I’d rather go with ‘inline or not’. If it’s not inline, it’s rubbish. It really is. Let’s start by considering the two kinds of table-valued function, and compare them. These functions are going to return the sales for a particular salesperson in a particular year, from the AdventureWorks database. CREATE FUNCTION dbo.FetchSales_inline(@salespersonid int, @orderyear int) RETURNS TABLE AS RETURN ( SELECT e.LoginID as EmployeeLogin, o.OrderDate, o.SalesOrderID FROM Sales.SalesOrderHeader AS o LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = o.SalesPersonID WHERE o.SalesPersonID = @salespersonid AND o.OrderDate >= DATEADD(year,@orderyear-2000,'20000101') AND o.OrderDate < DATEADD(year,@orderyear-2000+1,'20000101') ) ; GO CREATE FUNCTION dbo.FetchSales_multi(@salespersonid int, @orderyear int) RETURNS @results TABLE ( EmployeeLogin nvarchar(512), OrderDate datetime, SalesOrderID int ) AS BEGIN INSERT @results (EmployeeLogin, OrderDate, SalesOrderID) SELECT e.LoginID, o.OrderDate, o.SalesOrderID FROM Sales.SalesOrderHeader AS o LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = o.SalesPersonID WHERE o.SalesPersonID = @salespersonid AND o.OrderDate >= DATEADD(year,@orderyear-2000,'20000101') AND o.OrderDate < DATEADD(year,@orderyear-2000+1,'20000101') ; RETURN END ; GO You’ll notice that I’m being nice and responsible with the use of the DATEADD function, so that I have SARGability on the OrderDate filter. Regular readers will be hoping I’ll show what’s going on in the execution plans here. Here I’ve run two SELECT * queries with the “Show Actual Execution Plan” option turned on. Notice that the ‘Query cost’ of the multi-statement version is just 2% of the ‘Batch cost’. But also notice there’s trickery going on. And it’s nothing to do with that extra index that I have on the OrderDate column. Trickery. Look at it – clearly, the first plan is showing us what’s going on inside the function, but the second one isn’t. The second one is blindly running the function, and then scanning the results. There’s a Sequence operator which is calling the TVF operator, and then calling a Table Scan to get the results of that function for the SELECT operator. But surely it still has to do all the work that the first one is doing... To see what’s actually going on, let’s look at the Estimated plan. Now, we see the same plans (almost) that we saw in the Actuals, but we have an extra one – the one that was used for the TVF. Here’s where we see the inner workings of it. You’ll probably recognise the right-hand side of the TVF’s plan as looking very similar to the first plan – but it’s now being called by a stack of other operators, including an INSERT statement to be able to populate the table variable that the multi-statement TVF requires. And the cost of the TVF is 57% of the batch! But it gets worse. Let’s consider what happens if we don’t need all the columns. We’ll leave out the EmployeeLogin column. Here, we see that the inline function call has been simplified down. It doesn’t need the Employee table. The join is redundant and has been eliminated from the plan, making it even cheaper. But the multi-statement plan runs the whole thing as before, only removing the extra column when the Table Scan is performed. A multi-statement function is a lot more powerful than an inline one. An inline function can only be the result of a single sub-query. It’s essentially the same as a parameterised view, because views demonstrate this same behaviour of extracting the definition of the view and using it in the outer query. A multi-statement function is clearly more powerful because it can contain far more complex logic. But a multi-statement function isn’t really a function at all. It’s a stored procedure. It’s wrapped up like a function, but behaves like a stored procedure. It would be completely unreasonable to expect that a stored procedure could be simplified down to recognise that not all the columns might be needed, but yet this is part of the pain associated with this procedural function situation. The biggest clue that a multi-statement function is more like a stored procedure than a function is the “BEGIN” and “END” statements that surround the code. If you try to create a multi-statement function without these statements, you’ll get an error – they are very much required. When I used to present on this kind of thing, I even used to call it “The Dangers of BEGIN and END”, and yes, I’ve written about this type of thing before in a similarly-named post over at my old blog. Now how about scalar functions... Suppose we wanted a scalar function to return the count of these. CREATE FUNCTION dbo.FetchSales_scalar(@salespersonid int, @orderyear int) RETURNS int AS BEGIN RETURN ( SELECT COUNT(*) FROM Sales.SalesOrderHeader AS o LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = o.SalesPersonID WHERE o.SalesPersonID = @salespersonid AND o.OrderDate >= DATEADD(year,@orderyear-2000,'20000101') AND o.OrderDate < DATEADD(year,@orderyear-2000+1,'20000101') ); END ; GO Notice the evil words? They’re required. Try to remove them, you just get an error. That’s right – any scalar function is procedural, despite the fact that you wrap up a sub-query inside that RETURN statement. It’s as ugly as anything. Hopefully this will change in future versions. Let’s have a look at how this is reflected in an execution plan. Here’s a query, its Actual plan, and its Estimated plan: SELECT e.LoginID, y.year, dbo.FetchSales_scalar(p.SalesPersonID, y.year) AS NumSales FROM (VALUES (2001),(2002),(2003),(2004)) AS y (year) CROSS JOIN Sales.SalesPerson AS p LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = p.SalesPersonID; We see here that the cost of the scalar function is about twice that of the outer query. Nicely, the query optimizer has worked out that it doesn’t need the Employee table, but that’s a bit of a red herring here. There’s actually something way more significant going on. If I look at the properties of that UDF operator, it tells me that the Estimated Subtree Cost is 0.337999. If I just run the query SELECT dbo.FetchSales_scalar(281,2003); we see that the UDF cost is still unchanged. You see, this 0.0337999 is the cost of running the scalar function ONCE. But when we ran that query with the CROSS JOIN in it, we returned quite a few rows. 68 in fact. Could’ve been a lot more, if we’d had more salespeople or more years. And so we come to the biggest problem. This procedure (I don’t want to call it a function) is getting called 68 times – each one between twice as expensive as the outer query. And because it’s calling it in a separate context, there is even more overhead that I haven’t considered here. The cheek of it, to say that the Compute Scalar operator here costs 0%! I know a number of IT projects that could’ve used that kind of costing method, but that’s another story that I’m not going to go into here. Let’s look at a better way. Suppose our scalar function had been implemented as an inline one. Then it could have been expanded out like a sub-query. It could’ve run something like this: SELECT e.LoginID, y.year, (SELECT COUNT(*) FROM Sales.SalesOrderHeader AS o LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = o.SalesPersonID WHERE o.SalesPersonID = p.SalesPersonID AND o.OrderDate >= DATEADD(year,y.year-2000,'20000101') AND o.OrderDate < DATEADD(year,y.year-2000+1,'20000101') ) AS NumSales FROM (VALUES (2001),(2002),(2003),(2004)) AS y (year) CROSS JOIN Sales.SalesPerson AS p LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = p.SalesPersonID; Don’t worry too much about the Scan of the SalesOrderHeader underneath a Nested Loop. If you remember from plenty of other posts on the matter, execution plans don’t push the data through. That Scan only runs once. The Index Spool sucks the data out of it and populates a structure that is used to feed the Stream Aggregate. The Index Spool operator gets called 68 times, but the Scan only once (the Number of Executions property demonstrates this). Here, the Query Optimizer has a full picture of what’s being asked, and can make the appropriate decision about how it accesses the data. It can simplify it down properly. To get this kind of behaviour from a function, we need it to be inline. But without inline scalar functions, we need to make our function be table-valued. Luckily, that’s ok. CREATE FUNCTION dbo.FetchSales_inline2(@salespersonid int, @orderyear int) RETURNS table AS RETURN (SELECT COUNT(*) as NumSales FROM Sales.SalesOrderHeader AS o LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = o.SalesPersonID WHERE o.SalesPersonID = @salespersonid AND o.OrderDate >= DATEADD(year,@orderyear-2000,'20000101') AND o.OrderDate < DATEADD(year,@orderyear-2000+1,'20000101') ); GO But we can’t use this as a scalar. Instead, we need to use it with the APPLY operator. SELECT e.LoginID, y.year, n.NumSales FROM (VALUES (2001),(2002),(2003),(2004)) AS y (year) CROSS JOIN Sales.SalesPerson AS p LEFT JOIN HumanResources.Employee AS e ON e.EmployeeID = p.SalesPersonID OUTER APPLY dbo.FetchSales_inline2(p.SalesPersonID, y.year) AS n; And now, we get the plan that we want for this query. All we’ve done is tell the function that it’s returning a table instead of a single value, and removed the BEGIN and END statements. We’ve had to name the column being returned, but what we’ve gained is an actual inline simplifiable function. And if we wanted it to return multiple columns, it could do that too. I really consider this function to be superior to the scalar function in every way. It does need to be handled differently in the outer query, but in many ways it’s a more elegant method there too. The function calls can be put amongst the FROM clause, where they can then be used in the WHERE or GROUP BY clauses without fear of calling the function multiple times (another horrible side effect of functions). So please. If you see BEGIN and END in a function, remember it’s not really a function, it’s a procedure. And then fix it. @rob_farley

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Extending NerdDinner: Adding Geolocated Flair

- by Jon Galloway

NerdDinner is a website with the audacious goal of “Organizing the world’s nerds and helping them eat in packs.” Because nerds aren’t likely to socialize with others unless a website tells them to do it. Scott Hanselman showed off a lot of the cool features we’ve added to NerdDinner lately during his popular talk at MIX10, Beyond File | New Company: From Cheesy Sample to Social Platform. Did you miss it? Go ahead and watch it, I’ll wait. One of the features we wanted to add was flair. You know about flair, right? It’s a way to let folks who like your site show it off in their own site. For example, here’s my StackOverflow flair: Great! So how could we add some of this flair stuff to NerdDinner? What do we want to show? If we’re going to encourage our users to give up a bit of their beautiful website to show off a bit of ours, we need to think about what they’ll want to show. For instance, my StackOverflow flair is all about me, not StackOverflow. So how will this apply to NerdDinner? Since NerdDinner is all about organizing local dinners, in order for the flair to be useful it needs to make sense for the person viewing the web page. If someone visits from Egypt visits my blog, they should see information about NerdDinners in Egypt. That’s geolocation – localizing site content based on where the browser’s sitting, and it makes sense for flair as well as entire websites. So we’ll set up a simple little callout that prompts them to host a dinner in their area: Hopefully our flair works and there is a dinner near your viewers, so they’ll see another view which lists upcoming dinners near them: The Geolocation Part Generally website geolocation is done by mapping the requestor’s IP address to a geographic area. It’s not an exact science, but I’ve always found it to be pretty accurate. There are (at least) three ways to handle it: You pay somebody like MaxMind for a database (with regular updates) that sits on your server, and you use their API to do lookups. I used this on a pretty big project a few years ago and it worked well. You use HTML 5 Geolocation API or Google Gears or some other browser based solution. I think those are cool (I use Google Gears a lot), but they’re both in flux right now and I don’t think either has a wide enough of an install base yet to rely on them. You might want to, but I’ve heard you do all kinds of crazy stuff, and sometimes it gets you in trouble. I don’t mean talk out of line, but we all laugh behind your back a bit. But, hey, it’s up to you. It’s your flair or whatever. There are some free webservices out there that will take an IP address and give you location information. Easy, and works for everyone. That’s what we’re doing. I looked at a few different services and settled on IPInfoDB. It’s free, has a great API, and even returns JSON, which is handy for Javascript use. The IP query is pretty simple. We hit a URL like this: http://ipinfodb.com/ip_query.php?ip=74.125.45.100&timezone=false … and we get an XML response back like this… <?xml version="1.0" encoding="UTF-8"?> <Response> <Ip>74.125.45.100</Ip> <Status>OK</Status> <CountryCode>US</CountryCode> <CountryName>United States</CountryName> <RegionCode>06</RegionCode> <RegionName>California</RegionName> <City>Mountain View</City> <ZipPostalCode>94043</ZipPostalCode> <Latitude>37.4192</Latitude> <Longitude>-122.057</Longitude> </Response> So we’ll build some data transfer classes to hold the location information, like this: public class LocationInfo { public string Country { get; set; } public string RegionName { get; set; } public string City { get; set; } public string ZipPostalCode { get; set; } public LatLong Position { get; set; } } public class LatLong { public float Lat { get; set; } public float Long { get; set; } } And now hitting the service is pretty simple: public static LocationInfo HostIpToPlaceName(string ip) { string url = "http://ipinfodb.com/ip_query.php?ip={0}&timezone=false"; url = String.Format(url, ip); var result = XDocument.Load(url); var location = (from x in result.Descendants("Response") select new LocationInfo { City = (string)x.Element("City"), RegionName = (string)x.Element("RegionName"), Country = (string)x.Element("CountryName"), ZipPostalCode = (string)x.Element("CountryName"), Position = new LatLong { Lat = (float)x.Element("Latitude"), Long = (float)x.Element("Longitude") } }).First(); return location; } Getting The User’s IP Okay, but first we need the end user’s IP, and you’d think it would be as simple as reading the value from HttpContext: HttpContext.Current.Request.UserHostAddress But you’d be wrong. Sorry. UserHostAddress just wraps HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"], but that doesn’t get you the IP for users behind a proxy. That’s in another header, “HTTP_X_FORWARDED_FOR". So you can either hit a wrapper and then check a header, or just check two headers. I went for uniformity: string SourceIP = string.IsNullOrEmpty(Request.ServerVariables["HTTP_X_FORWARDED_FOR"]) ? Request.ServerVariables["REMOTE_ADDR"] : Request.ServerVariables["HTTP_X_FORWARDED_FOR"]; We’re almost set to wrap this up, but first let’s talk about our views. Yes, views, because we’ll have two. Selecting the View We wanted to make it easy for people to include the flair in their sites, so we looked around at how other people were doing this. The StackOverflow folks have a pretty good flair system, which allows you to include the flair in your site as either an IFRAME reference or a Javascript include. We’ll do both. We have a ServicesController to handle use of the site information outside of NerdDinner.com, so this fits in pretty well there. We’ll be displaying the same information for both HTML and Javascript flair, so we can use one Flair controller action which will return a different view depending on the requested format. Here’s our general flow for our controller action: Get the user’s IP Translate it to a location Grab the top three upcoming dinners that are near that location Select the view based on the format (defaulted to “html”) Return a FlairViewModel which contains the list of dinners and the location information public ActionResult Flair(string format = "html") { string SourceIP = string.IsNullOrEmpty( Request.ServerVariables["HTTP_X_FORWARDED_FOR"]) ? Request.ServerVariables["REMOTE_ADDR"] : Request.ServerVariables["HTTP_X_FORWARDED_FOR"]; var location = GeolocationService.HostIpToPlaceName(SourceIP); var dinners = dinnerRepository. FindByLocation(location.Position.Lat, location.Position.Long). OrderByDescending(p => p.EventDate).Take(3); // Select the view we'll return. // Using a switch because we'll add in JSON and other formats later. string view; switch (format.ToLower()) { case "javascript": view = "JavascriptFlair"; break; default: view = "Flair"; break; } return View( view, new FlairViewModel { Dinners = dinners.ToList(), LocationName = string.IsNullOrEmpty(location.City) ? "you" : String.Format("{0}, {1}", location.City, location.RegionName) } ); } Note: I’m not in love with the logic here, but it seems like overkill to extract the switch statement away when we’ll probably just have two or three views. What do you think? The HTML View The HTML version of the view is pretty simple – the only thing of any real interest here is the use of an extension method to truncate strings that are would cause the titles to wrap. public static string Truncate(this string s, int maxLength) { if (string.IsNullOrEmpty(s) || maxLength <= 0) return string.Empty; else if (s.Length > maxLength) return s.Substring(0, maxLength) + "..."; else return s; } So here’s how the HTML view ends up looking: <%@ Page Title="" Language="C#" Inherits="System.Web.Mvc.ViewPage<FlairViewModel>" %> <%@ Import Namespace="NerdDinner.Helpers" %> <%@ Import Namespace="NerdDinner.Models" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Nerd Dinner</title> <link href="/Content/Flair.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="nd-wrapper"> <h2 id="nd-header">NerdDinner.com</h2> <div id="nd-outer"> <% if (Model.Dinners.Count == 0) { %> <div id="nd-bummer"> Looks like there's no Nerd Dinners near <%:Model.LocationName %> in the near future. Why not <a target="_blank" href="http://www.nerddinner.com/Dinners/Create">host one</a>?</div> <% } else { %> <h3> Dinners Near You</h3> <ul> <% foreach (var item in Model.Dinners) { %> <li> <%: Html.ActionLink(String.Format("{0} with {1} on {2}", item.Title.Truncate(20), item.HostedBy, item.EventDate.ToShortDateString()), "Details", "Dinners", new { id = item.DinnerID }, new { target = "_blank" })%></li> <% } %> </ul> <% } %> <div id="nd-footer"> More dinners and fun at <a target="_blank" href="http://nrddnr.com">http://nrddnr.com</a></div> </div> </div> </body> </html> You’d include this in a page using an IFRAME, like this: <IFRAME height=230 marginHeight=0 src="http://nerddinner.com/services/flair" frameBorder=0 width=160 marginWidth=0 scrolling=no></IFRAME> The Javascript view The Javascript flair is written so you can include it in a webpage with a simple script include, like this: <script type="text/javascript" src="http://nerddinner.com/services/flair?format=javascript"></script> The goal of this view is very similar to the HTML embed view, with a few exceptions: We’re creating a script element and adding it to the head of the document, which will then document.write out the content. Note that you have to consider if your users will actually have a <head> element in their documents, but for website flair use cases I think that’s a safe bet. Since the content is being added to the existing page rather than shown in an IFRAME, all links need to be absolute. That means we can’t use Html.ActionLink, since it generates relative routes. We need to escape everything since it’s being written out as strings. We need to set the content type to application/x-javascript. The easiest way to do that is to use the <%@ Page ContentType%> directive. <%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<NerdDinner.Models.FlairViewModel>" ContentType="application/x-javascript" %> <%@ Import Namespace="NerdDinner.Helpers" %> <%@ Import Namespace="NerdDinner.Models" %> document.write('<script>var link = document.createElement(\"link\");link.href = \"http://nerddinner.com/content/Flair.css\";link.rel = \"stylesheet\";link.type = \"text/css\";var head = document.getElementsByTagName(\"head\")[0];head.appendChild(link);</script>'); document.write('<div id=\"nd-wrapper\"><h2 id=\"nd-header\">NerdDinner.com</h2><div id=\"nd-outer\">'); <% if (Model.Dinners.Count == 0) { %> document.write('<div id=\"nd-bummer\">Looks like there\'s no Nerd Dinners near <%:Model.LocationName %> in the near future. Why not <a target=\"_blank\" href=\"http://www.nerddinner.com/Dinners/Create\">host one</a>?</div>'); <% } else { %> document.write('<h3> Dinners Near You</h3><ul>'); <% foreach (var item in Model.Dinners) { %> document.write('<li><a target=\"_blank\" href=\"http://nrddnr.com/<%: item.DinnerID %>\"><%: item.Title.Truncate(20) %> with <%: item.HostedBy %> on <%: item.EventDate.ToShortDateString() %></a></li>'); <% } %> document.write('</ul>'); <% } %> document.write('<div id=\"nd-footer\"> More dinners and fun at <a target=\"_blank\" href=\"http://nrddnr.com\">http://nrddnr.com</a></div></div></div>'); Getting IP’s for Testing There are a variety of online services that will translate a location to an IP, which were handy for testing these out. I found http://www.itouchmap.com/latlong.html to be most useful, but I’m open to suggestions if you know of something better. Next steps I think the next step here is to minimize load – you know, in case people start actually using this flair. There are two places to think about – the NerdDinner.com servers, and the services we’re using for Geolocation. I usually think about caching as a first attack on server load, but that’s less helpful here since every user will have a different IP. Instead, I’d look at taking advantage of Asynchronous Controller Actions, a cool new feature in ASP.NET MVC 2. Async Actions let you call a potentially long-running webservice without tying up a thread on the server while waiting for the response. There’s some good info on that in the MSDN documentation, and Dino Esposito wrote a great article on Asynchronous ASP.NET Pages in the April 2010 issue of MSDN Magazine. But let’s think of the children, shall we? What about ipinfodb.com? Well, they don’t have specific daily limits, but they do throttle you if you put a lot of traffic on them. From their FAQ: We do not have a specific daily limit but queries that are at a rate faster than 2 per second will be put in "queue". If you stay below 2 queries/second everything will be normal. If you go over the limit, you will still get an answer for all queries but they will be slowed down to about 1 per second. This should not affect most users but for high volume websites, you can either use our IP database on your server or we can whitelist your IP for 5$/month (simply use the donate form and leave a comment with your server IP). Good programming practices such as not querying our API for all page views (you can store the data in a cookie or a database) will also help not reaching the limit. So the first step there is to save the geolocalization information in a time-limited cookie, which will allow us to look up the local dinners immediately without having to hit the geolocation service.

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Auto blocking attacking IP address

- by dong

This is to share my PowerShell code online. I original asked this question on MSDN forum (or TechNet?) here: http://social.technet.microsoft.com/Forums/en-US/winserversecurity/thread/f950686e-e3f8-4cf2-b8ec-2685c1ed7a77 In short, this is trying to find attacking IP address then add it into Firewall block rule. So I suppose: 1, You are running a Windows Server 2008 facing the Internet. 2, You need to have some port open for service, e.g. TCP 21 for FTP; TCP 3389 for Remote Desktop. You can see in my code I’m only dealing with these two since that’s what I opened. You can add further port number if you like, but the way to process might be different with these two. 3, I strongly suggest you use STRONG password and follow all security best practices, this ps1 code is NOT for adding security to your server, but reduce the nuisance from brute force attack, and make sys admin’s life easier: i.e. your FTP log won’t hold megabytes of nonsense, your Windows system log will not roll back and only can tell you what happened last month. 4, You are comfortable with setting up Windows Firewall rules, in my code, my rule has a name of “MY BLACKLIST”, you need to setup a similar one, and set it to BLOCK everything. 5, My rule is dangerous because it has the risk to block myself out as well. I do have a backup plan i.e. the DELL DRAC5 so that if that happens, I still can remote console to my server and reset the firewall. 6, By no means the code is perfect, the coding style, the use of PowerShell skills, the hard coded part, all can be improved, it’s just that it’s good enough for me already. It has been running on my server for more than 7 MONTHS. 7, Current code still has problem, I didn’t solve it yet, further on this point after the code. :) #Dong Xie, March 2012 #my simple code to monitor attack and deal with it #Windows Server 2008 Logon Type #8: NetworkCleartext, i.e. FTP #10: RemoteInteractive, i.e. RDP $tick = 0; "Start to run at: " + (get-date); $regex1 = [regex] "192\.168\.100\.(?:101|102):3389\s+(\d+\.\d+\.\d+\.\d+)"; $regex2 = [regex] "Source Network Address:\t(\d+\.\d+\.\d+\.\d+)"; while($True) { $blacklist = @(); "Running... (tick:" + $tick + ")"; $tick+=1; #Port 3389 $a = @() netstat -no | Select-String ":3389" | ? { $m = $regex1.Match($_); ` $ip = $m.Groups[1].Value; if ($m.Success -and $ip -ne "10.0.0.1") {$a = $a + $ip;} } if ($a.count -gt 0) { $ips = get-eventlog Security -Newest 1000 | Where-Object {$_.EventID -eq 4625 -and $_.Message -match "Logon Type:\s+10"} | foreach { ` $m = $regex2.Match($_.Message); $ip = $m.Groups[1].Value; $ip; } | Sort-Object | Tee-Object -Variable list | Get-Unique foreach ($ip in $a) { if ($ips -contains $ip) { if (-not ($blacklist -contains $ip)) { $attack_count = ($list | Select-String $ip -SimpleMatch | Measure-Object).count; "Found attacking IP on 3389: " + $ip + ", with count: " + $attack_count; if ($attack_count -ge 20) {$blacklist = $blacklist + $ip;} } } } } #FTP $now = (Get-Date).AddMinutes(-5); #check only last 5 mins. #Get-EventLog has built-in switch for EventID, Message, Time, etc. but using any of these it will be VERY slow. $count = (Get-EventLog Security -Newest 1000 | Where-Object {$_.EventID -eq 4625 -and $_.Message -match "Logon Type:\s+8" -and ` $_.TimeGenerated.CompareTo($now) -gt 0} | Measure-Object).count; if ($count -gt 50) #threshold { $ips = @(); $ips1 = dir "C:\inetpub\logs\LogFiles\FPTSVC2" | Sort-Object -Property LastWriteTime -Descending ` | select -First 1 | gc | select -Last 200 | where {$_ -match "An\+error\+occured\+during\+the\+authentication\+process."} ` | Select-String -Pattern "(\d+\.\d+\.\d+\.\d+)" | select -ExpandProperty Matches | select -ExpandProperty value | Group-Object ` | where {$_.Count -ge 10} | select -ExpandProperty Name; $ips2 = dir "C:\inetpub\logs\LogFiles\FTPSVC3" | Sort-Object -Property LastWriteTime -Descending ` | select -First 1 | gc | select -Last 200 | where {$_ -match "An\+error\+occured\+during\+the\+authentication\+process."} ` | Select-String -Pattern "(\d+\.\d+\.\d+\.\d+)" | select -ExpandProperty Matches | select -ExpandProperty value | Group-Object ` | where {$_.Count -ge 10} | select -ExpandProperty Name; $ips += $ips1; $ips += $ips2; $ips = $ips | where {$_ -ne "10.0.0.1"} | Sort-Object | Get-Unique; foreach ($ip in $ips) { if (-not ($blacklist -contains $ip)) { "Found attacking IP on FTP: " + $ip; $blacklist = $blacklist + $ip; } } } #Firewall change <# $current = (netsh advfirewall firewall show rule name="MY BLACKLIST" | where {$_ -match "RemoteIP"}).replace("RemoteIP:", "").replace(" ","").replace("/255.255.255.255",""); #inside $current there is no \r or \n need remove. foreach ($ip in $blacklist) { if (-not ($current -match $ip) -and -not ($ip -like "10.0.0.*")) {"Adding this IP into firewall blocklist: " + $ip; $c= 'netsh advfirewall firewall set rule name="MY BLACKLIST" new RemoteIP="{0},{1}"' -f $ip, $current; Invoke-Expression $c; } } #> foreach ($ip in $blacklist) { $fw=New-object –comObject HNetCfg.FwPolicy2; # http://blogs.technet.com/b/jamesone/archive/2009/02/18/how-to-manage-the-windows-firewall-settings-with-powershell.aspx $myrule = $fw.Rules | where {$_.Name -eq "MY BLACKLIST"} | select -First 1; # Potential bug here? if (-not ($myrule.RemoteAddresses -match $ip) -and -not ($ip -like "10.0.0.*")) {"Adding this IP into firewall blocklist: " + $ip; $myrule.RemoteAddresses+=(","+$ip); } } Wait-Event -Timeout 30 #pause 30 secs } # end of top while loop. Further points: 1, I suppose the server is listening on port 3389 on server IP: 192.168.100.101 and 192.168.100.102, you need to replace that with your real IP. 2, I suppose you are Remote Desktop to this server from a workstation with IP: 10.0.0.1. Please replace as well. 3, The threshold for 3389 attack is 20, you don’t want to block yourself just because you typed your password wrong 3 times, you can change this threshold by your own reasoning. 4, FTP is checking the log for attack only to the last 5 mins, you can change that as well. 5, I suppose the server is serving FTP on both IP address and their LOG path are C:\inetpub\logs\LogFiles\FPTSVC2 and C:\inetpub\logs\LogFiles\FPTSVC3. Change accordingly. 6, FTP checking code is only asking for the last 200 lines of log, and the threshold is 10, change as you wish. 7, the code runs in a loop, you can set the loop time at the last line. To run this code, copy and paste to your editor, finish all the editing, get it to your server, and open an CMD window, then type powershell.exe –file your_powershell_file_name.ps1, it will start running, you can Ctrl-C to break it. This is what you see when it’s running: This is when it detected attack and adding the firewall rule: Regarding the design of the code: 1, There are many ways you can detect the attack, but to add an IP into a block rule is no small thing, you need to think hard before doing it, reason for that may include: You don’t want block yourself; and not blocking your customer/user, i.e. the good guy. 2, Thus for each service/port, I double check. For 3389, first it needs to show in netstat.exe, then the Event log; for FTP, first check the Event log, then the FTP log files. 3, At three places I need to make sure I’m not adding myself into the block rule. –ne with single IP, –like with subnet. Now the final bit: 1, The code will stop working after a while (depends on how busy you are attacked, could be weeks, months, or days?!) It will throw Red error message in CMD, don’t Panic, it does no harm, but it also no longer blocking new attack. THE REASON is not confirmed with MS people: the COM object to manage firewall, you can only give it a list of IP addresses to the length of around 32KB I think, once it reaches the limit, you get the error message. 2, This is in fact my second solution to use the COM object, the first solution is still in the comment block for your reference, which is using netsh, that fails because being run from CMD, you can only throw it a list of IP to 8KB. 3, I haven’t worked the workaround yet, some ideas include: wrap that RemoteAddresses setting line with error checking and once it reaches the limit, use the newly detected IP to be the list, not appending to it. This basically reset your block rule to ground zero and lose the previous bad IPs. This does no harm as it sounds, because given a certain period has passed, any these bad IPs still not repent and continue the attack to you, it only got 30 seconds or 20 guesses of your password before you block it again. And there is the benefit that the bad IP may turn back to the good hands again, and you are not blocking a potential customer or your CEO’s home pc because once upon a time, it’s a zombie. Thus the ZEN of blocking: never block any IP for too long. 4, But if you insist to block the ugly forever, my other ideas include: You call MS support, ask them how can we set an arbitrary length of IP addresses in a rule; at least from my experiences at the Forum, they don’t know and they don’t care, because they think the dynamic blocking should be done by some expensive hardware. Or, from programming perspective, you can create a new rule once the old is full, then you’ll have MY BLACKLIST1, MY BLACKLIST2, MY BLACKLIST3, … etc. Once in a while you can compile them together and start a business to sell your blacklist on the market! Enjoy the code! p.s. (PowerShell is REALLY REALLY GREAT!)

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Sorting Algorithms

- by MarkPearl

General Every time I go back to university I find myself wading through sorting algorithms and their implementation in C++. Up to now I haven’t really appreciated their true value. However as I discovered this last week with Dictionaries in C# – having a knowledge of some basic programming principles can greatly improve the performance of a system and make one think twice about how to tackle a problem. I’m going to cover briefly in this post the following: Selection Sort Insertion Sort Shellsort Quicksort Mergesort Heapsort (not complete) Selection Sort Array based selection sort is a simple approach to sorting an unsorted array. Simply put, it repeats two basic steps to achieve a sorted collection. It starts with a collection of data and repeatedly parses it, each time sorting out one element and reducing the size of the next iteration of parsed data by one. So the first iteration would go something like this… Go through the entire array of data and find the lowest value Place the value at the front of the array The second iteration would go something like this… Go through the array from position two (position one has already been sorted with the smallest value) and find the next lowest value in the array. Place the value at the second position in the array This process would be completed until the entire array had been sorted. A positive about selection sort is that it does not make many item movements. In fact, in a worst case scenario every items is only moved once. Selection sort is however a comparison intensive sort. If you had 10 items in a collection, just to parse the collection you would have 10+9+8+7+6+5+4+3+2=54 comparisons to sort regardless of how sorted the collection was to start with. If you think about it, if you applied selection sort to a collection already sorted, you would still perform relatively the same number of iterations as if it was not sorted at all. Many of the following algorithms try and reduce the number of comparisons if the list is already sorted – leaving one with a best case and worst case scenario for comparisons. Likewise different approaches have different levels of item movement. Depending on what is more expensive, one may give priority to one approach compared to another based on what is more expensive, a comparison or a item move. Insertion Sort Insertion sort tries to reduce the number of key comparisons it performs compared to selection sort by not “doing anything” if things are sorted. Assume you had an collection of numbers in the following order… 10 18 25 30 23 17 45 35 There are 8 elements in the list. If we were to start at the front of the list – 10 18 25 & 30 are already sorted. Element 5 (23) however is smaller than element 4 (30) and so needs to be repositioned. We do this by copying the value at element 5 to a temporary holder, and then begin shifting the elements before it up one. So… Element 5 would be copied to a temporary holder 10 18 25 30 23 17 45 35 – T 23 Element 4 would shift to Element 5 10 18 25 30 30 17 45 35 – T 23 Element 3 would shift to Element 4 10 18 25 25 30 17 45 35 – T 23 Element 2 (18) is smaller than the temporary holder so we put the temporary holder value into Element 3. 10 18 23 25 30 17 45 35 – T 23 We now have a sorted list up to element 6. And so we would repeat the same process by moving element 6 to a temporary value and then shifting everything up by one from element 2 to element 5. As you can see, one major setback for this technique is the shifting values up one – this is because up to now we have been considering the collection to be an array. If however the collection was a linked list, we would not need to shift values up, but merely remove the link from the unsorted value and “reinsert” it in a sorted position. Which would reduce the number of transactions performed on the collection. So.. Insertion sort seems to perform better than selection sort – however an implementation is slightly more complicated. This is typical with most sorting algorithms – generally, greater performance leads to greater complexity. Also, insertion sort performs better if a collection of data is already sorted. If for instance you were handed a sorted collection of size n, then only n number of comparisons would need to be performed to verify that it is sorted. It’s important to note that insertion sort (array based) performs a number item moves – every time an item is “out of place” several items before it get shifted up. Shellsort – Diminishing Increment Sort So up to now we have covered Selection Sort & Insertion Sort. Selection Sort makes many comparisons and insertion sort (with an array) has the potential of making many item movements. Shellsort is an approach that takes the normal insertion sort and tries to reduce the number of item movements. In Shellsort, elements in a collection are viewed as sub-collections of a particular size. Each sub-collection is sorted so that the elements that are far apart move closer to their final position. Suppose we had a collection of 15 elements… 10 20 15 45 36 48 7 60 18 50 2 19 43 30 55 First we may view the collection as 7 sub-collections and sort each sublist, lets say at intervals of 7 10 60 55 – 20 18 – 15 50 – 45 2 – 36 19 – 48 43 – 7 30 10 55 60 – 18 20 – 15 50 – 2 45 – 19 36 – 43 48 – 7 30 (Sorted) We then sort each sublist at a smaller inter – lets say 4 10 55 60 18 – 20 15 50 2 – 45 19 36 43 – 48 7 30 10 18 55 60 – 2 15 20 50 – 19 36 43 45 – 7 30 48 (Sorted) We then sort elements at a distance of 1 (i.e. we apply a normal insertion sort) 10 18 55 60 2 15 20 50 19 36 43 45 7 30 48 2 7 10 15 18 19 20 30 36 43 45 48 50 55 (Sorted) The important thing with shellsort is deciding on the increment sequence of each sub-collection. From what I can tell, there isn’t any definitive method and depending on the order of your elements, different increment sequences may perform better than others. There are however certain increment sequences that you may want to avoid. An even based increment sequence (e.g. 2 4 8 16 32 …) should typically be avoided because it does not allow for even elements to be compared with odd elements until the final sort phase – which in a way would negate many of the benefits of using sub-collections. The performance on the number of comparisons and item movements of Shellsort is hard to determine, however it is considered to be considerably better than the normal insertion sort. Quicksort Quicksort uses a divide and conquer approach to sort a collection of items. The collection is divided into two sub-collections – and the two sub-collections are sorted and combined into one list in such a way that the combined list is sorted. The algorithm is in general pseudo code below… Divide the collection into two sub-collections Quicksort the lower sub-collection Quicksort the upper sub-collection Combine the lower & upper sub-collection together As hinted at above, quicksort uses recursion in its implementation. The real trick with quicksort is to get the lower and upper sub-collections to be of equal size. The size of a sub-collection is determined by what value the pivot is. Once a pivot is determined, one would partition to sub-collections and then repeat the process on each sub collection until you reach the base case. With quicksort, the work is done when dividing the sub-collections into lower & upper collections. The actual combining of the lower & upper sub-collections at the end is relatively simple since every element in the lower sub-collection is smaller than the smallest element in the upper sub-collection. Mergesort With quicksort, the average-case complexity was O(nlog2n) however the worst case complexity was still O(N*N). Mergesort improves on quicksort by always having a complexity of O(nlog2n) regardless of the best or worst case. So how does it do this? Mergesort makes use of the divide and conquer approach to partition a collection into two sub-collections. It then sorts each sub-collection and combines the sorted sub-collections into one sorted collection. The general algorithm for mergesort is as follows… Divide the collection into two sub-collections Mergesort the first sub-collection Mergesort the second sub-collection Merge the first sub-collection and the second sub-collection As you can see.. it still pretty much looks like quicksort – so lets see where it differs… Firstly, mergesort differs from quicksort in how it partitions the sub-collections. Instead of having a pivot – merge sort partitions each sub-collection based on size so that the first and second sub-collection of relatively the same size. This dividing keeps getting repeated until the sub-collections are the size of a single element. If a sub-collection is one element in size – it is now sorted! So the trick is how do we put all these sub-collections together so that they maintain their sorted order. Sorted sub-collections are merged into a sorted collection by comparing the elements of the sub-collection and then adjusting the sorted collection. Lets have a look at a few examples… Assume 2 sub-collections with 1 element each 10 & 20 Compare the first element of the first sub-collection with the first element of the second sub-collection. Take the smallest of the two and place it as the first element in the sorted collection. In this scenario 10 is smaller than 20 so 10 is taken from sub-collection 1 leaving that sub-collection empty, which means by default the next smallest element is in sub-collection 2 (20). So the sorted collection would be 10 20 Lets assume 2 sub-collections with 2 elements each 10 20 & 15 19 So… again we would Compare 10 with 15 – 10 is the winner so we add it to our sorted collection (10) leaving us with 20 & 15 19 Compare 20 with 15 – 15 is the winner so we add it to our sorted collection (10 15) leaving us with 20 & 19 Compare 20 with 19 – 19 is the winner so we add it to our sorted collection (10 15 19) leaving us with 20 & _ 20 is by default the winner so our sorted collection is 10 15 19 20. Make sense? Heapsort (still needs to be completed) So by now I am tired of sorting algorithms and trying to remember why they were so important. I think every year I go through this stuff I wonder to myself why are we made to learn about selection sort and insertion sort if they are so bad – why didn’t we just skip to Mergesort & Quicksort. I guess the only explanation I have for this is that sometimes you learn things so that you can implement them in future – and other times you learn things so that you know it isn’t the best way of implementing things and that you don’t need to implement it in future. Anyhow… luckily this is going to be the last one of my sorts for today. The first step in heapsort is to convert a collection of data into a heap. After the data is converted into a heap, sorting begins… So what is the definition of a heap? If we have to convert a collection of data into a heap, how do we know when it is a heap and when it is not? The definition of a heap is as follows: A heap is a list in which each element contains a key, such that the key in the element at position k in the list is at least as large as the key in the element at position 2k +1 (if it exists) and 2k + 2 (if it exists). Does that make sense? At first glance I’m thinking what the heck??? But then after re-reading my notes I see that we are doing something different – up to now we have really looked at data as an array or sequential collection of data that we need to sort – a heap represents data in a slightly different way – although the data is stored in a sequential collection, for a sequential collection of data to be in a valid heap – it is “semi sorted”. Let me try and explain a bit further with an example… Example 1 of Potential Heap Data Assume we had a collection of numbers as follows 1[1] 2[2] 3[3] 4[4] 5[5] 6[6] For this to be a valid heap element with value of 1 at position [1] needs to be greater or equal to the element at position [3] (2k +1) and position [4] (2k +2). So in the above example, the collection of numbers is not in a valid heap. Example 2 of Potential Heap Data Lets look at another collection of numbers as follows 6[1] 5[2] 4[3] 3[4] 2[5] 1[6] Is this a valid heap? Well… element with the value 6 at position 1 must be greater or equal to the element at position [3] and position [4]. Is 6 > 4 and 6 > 3? Yes it is. Lets look at element 5 as position 2. It must be greater than the values at [4] & [5]. Is 5 > 3 and 5 > 2? Yes it is. If you continued to examine this second collection of data you would find that it is in a valid heap based on the definition of a heap.

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You should NOT be writing jQuery in SharePoint if…

- by Mark Rackley

Yes… another one of these posts. What can I say? I’m a pot stirrer.. a rabble rouser *rabble rabble* jQuery in SharePoint seems to be a fairly polarizing issue with one side thinking it is the most awesome thing since Princess Leia as the slave girl in Return of the Jedi and the other half thinking it is the worst idea since Mannequin 2: On the Move. The correct answer is OF COURSE “it depends”. But what are those deciding factors that make jQuery an awesome fit or leave a bad taste in your mouth? Let’s see if I can drive the discussion here with some polarizing comments of my own… I know some of you are getting ready to leave your comments even now before reading the rest of the blog, which is great! Iron sharpens iron… These discussions hopefully open us up to understanding the entire process better and think about things in a different way. You should not be writing jQuery in SharePoint if you are not a developer… Let’s start off with my most polarizing and rant filled portion of the blog post. If you don’t know what you are doing or you don’t have a background that helps you understand the implications of what you are writing then you should not be writing jQuery in SharePoint! I truly believe that one of the biggest reasons for the jQuery haters is because of all the bad jQuery out there. If you don’t know what you are doing you can do some NASTY things! One of the best stories I’ve heard about this is from my good friend John Ferringer (@ferringer). John tells this story during our Mythbusters session we do together. One of his clients was undergoing a Denial of Service attack and they couldn’t figure out what was going on! After much searching they found that some genius jQuery developer wrote some code for an image rotator, but did not take into account what happens when there are no images to load! The code just kept hitting the servers over and over and over again which prevented anything else from getting done! Now, I’m NOT saying that I have not done the same sort of thing in the past or am immune from such mistakes. My point is that if you don’t know what you are doing, there are very REAL consequences that can have a major impact on your organization AND they will be hard to track down. Think how happy your boss will be after you copy and pasted some jQuery from a blog without understanding what it does, it brings down the farm, AND it takes them 3 days to track it back to you. :/ Good times will not be had. Like it or not JavaScript/jQuery is a programming language. While you .NET people sit on your high horses because your code is compiled and “runs faster” (also debatable), the rest of us will be actually getting work done and delivering solutions while you are trying to figure out why your widget won’t deploy. I can pick at that scab because I write .NET code too and speak from experience. I can do both, and do both well. So, I am not speaking from ignorance here. In JavaScript/jQuery you have variables, loops, conditionals, functions, arrays, events, and built in methods. If you are not a developer you just aren’t going to take advantage of all of that and use it correctly. Ahhh.. but there is hope! There is a lot of jQuery resources out there to help you learn and learn well! There are many experts on the subject that will gladly tell you when you are smoking crack. I just this minute saw a tweet from @cquick with a link to: “jQuery Fundamentals”. I just glanced through it and this may be a great primer for you aspiring jQuery devs. Take advantage of all the resources and become a developer! Hey, it will look awesome on your resume right? You should not be writing jQuery in SharePoint if it depends too much on client resources for a good user experience I’ve said it once and I’ll say it over and over until you understand. jQuery is executed on the client’s computer. Got it? If you are looping through hundreds of rows of data, searching through an enormous DOM, or performing many calculations it is going to take some time! AND if your user happens to be sitting on some old PC somewhere that they picked up at a garage sale their experience will be that much worse! If you can’t give the user a good experience they will not use the site. So, if jQuery is causing the user to have a bad experience, don’t use it. I sometimes go as far to say that you should NOT go to jQuery as a first option for external facing web sites because you have ZERO control over what the end user’s computer will be. You just can’t guarantee an awesome user experience all of the time. Ahhh… but you have no choice? (where have I heard that before?). Well… if you really have no choice, here are some tips to help improve the experience: Avoid screen scraping This is not 1999 and SharePoint is not an old green screen from a mainframe… so why are you treating it like it is? Screen scraping is time consuming and client intensive. Take advantage of tools like SPServices to do your data retrieval when possible. Fine tune your DOM searches A lot of time can be eaten up just searching the DOM and ignoring table rows that you don’t need. Write better jQuery to only loop through tables rows that you need, or only access specific elements you need. Take advantage of Element ID’s to return the one element you are looking for instead of looping through all the DOM over and over again. Write better jQuery Remember this is development. Think about how you can write cleaner, faster jQuery. This directly relates to the previous point of improving your DOM searches, but also when using arrays, variables and loops. Do you REALLY need to loop through that array 3 times? How can you knock it down to 2 times or even 1? When you have lots of calculations and data that you are manipulating every operation adds up. Think about how you can streamline it. Back in the old days before RAM was abundant, Cores were plentiful and dinosaurs roamed the earth, us developers had to take performance into account in everything we did. It’s a lost art that really needs to be used here. You should not be writing jQuery in SharePoint if you are sending a lot of data over the wire… Developer: “Awesome… you can easily call SharePoint’s web services to retrieve and write data using SPServices!” Administrator: “Crap! you can easily call SharePoint’s web services to retrieve and write data using SPServices!” SPServices may indeed be the best thing that happened to SharePoint since the invention of SharePoint Saturdays by Godfather Lotter… BUT you HAVE to use it wisely! (I REFUSE to make the Spiderman reference). If you do not know what you are doing your code will bring back EVERY field and EVERY row from a list and push that over the internet with all that lovely XML wrapped around it. That can be a HUGE amount of data and will GREATLY impact performance! Calling several web service methods at the same time can cause the same problem and can negatively impact your SharePoint servers. These problems, thankfully, are not difficult to rectify if you are careful: Limit list data retrieved Use CAML to reduce the number of rows returned and limit the fields returned using ViewFields. You should definitely be doing this regardless. If you aren’t I hope your admin thumps you upside the head. Batch large list updates You may or may not have noticed that if you try to do large updates (hundreds of rows) that the performance is either completely abysmal or it fails over half the time. You can greatly improve performance and avoid timeouts by breaking up your updates into several smaller updates. I don’t know if there is a magic number for best performance, it really depends on how much data you are sending back more than the number of rows. However, I have found that 200 rows generally works well. Play around and find the right number for your situation. Delay Web Service calls when possible One of the cool things about jQuery and SPServices is that you can delay queries to the server until they are actually needed instead of doing them all at once. This can lead to performance improvements over DataViewWebParts and even .NET code in the right situations. So, don’t load the data until it’s needed. In some instances you may not need to retrieve the data at all, so why retrieve it ALL the time? You should not be writing jQuery in SharePoint if there is a better solution… jQuery is NOT the silver bullet in SharePoint, it is not the answer to every question, it is just another tool in the developers toolkit. I urge all developers to know what options exist out there and choose the right one! Sometimes it will be jQuery, sometimes it will be .NET, sometimes it will be XSL, and sometimes it will be some other choice… So, when is there a better solution to jQuery? When you can’t get away from performance problems Sometimes jQuery will just give you horrible performance regardless of what you do because of unavoidable obstacles. In these situations you are going to have to figure out an alternative. Can I do it with a DVWP or do I have to crack open Visual Studio? When you need to do something that jQuery can’t do There are lots of things you can’t do in jQuery like elevate privileges, event handlers, workflows, or interact with back end systems that have no web service interface. It just can’t do everything. When it can be done faster and more efficiently another way Why are you spending time to write jQuery to do a DataViewWebPart that would take 5 minutes? Or why are you trying to implement complicated logic that would be simple to do in .NET? If your answer is that you don’t have the option, okay. BUT if you do have the option don’t reinvent the wheel! Take advantage of the other tools. The answer is not always jQuery… sorry… the kool-aid tastes good, but sweet tea is pretty awesome too. You should not be using jQuery in SharePoint if you are a moron… Let’s finish up the blog on a high note… Yes.. it’s true, I sometimes type things just to get a reaction… guess this section title might be a good example, but it feels good sometimes just to type the words that a lot of us think… So.. don’t be that guy! Another good buddy of mine that works for Microsoft told me. “I loved jQuery in SharePoint…. until I had to support it.”. He went on to explain that some user was making several web service calls on a page using jQuery and then was calling Microsoft and COMPLAINING because the page took so long to load… DUH! What do you expect to happen when you are pushing that much data over the wire and are making that many web service calls at once!! It’s one thing to write that kind of code and accept it’s just going to take a while, it’s COMPLETELY another issue to do that and then complain when it’s not lightning fast! Someone’s gene pool needs some chlorine. So, I think this is a nice summary of the blog… DON’T be that guy… don’t be a moron. How can you stop yourself from being a moron? Ah.. glad you asked, here are some tips: Think Is jQuery the right solution to my problem? Is there a better approach? What are the implications and pitfalls of using jQuery in this situation? Search What are others doing? Does someone have a better solution? Is there a third party library that does the same thing I need? Plan Write good jQuery. Limit calculations and data sent over the wire and don’t reinvent the wheel when possible. Test Okay, it works well on your machine. Try it on others ESPECIALLY if this is for an external site. Test with empty data. Test with hundreds of rows of data. Test as many scenarios as possible. Monitor those server resources to see the impact there as well. Ask the experts As smart as you are, there are people smarter than you. Even the experts talk to each other to make sure they aren't doing something stupid. And for the MOST part they are pretty nice guys. Marc Anderson and Christophe Humbert are two guys who regularly keep me in line. Make sure you aren’t doing something stupid. Repeat So, when you think you have the best solution possible, repeat the steps above just to be safe. Conclusion jQuery is an awesome tool and has come in handy on many occasions. I’m even teaching a 1/2 day SharePoint & jQuery workshop at the upcoming SPTechCon in Boston if you want to berate me in person. However, it’s only as awesome as the developer behind the keyboard. It IS development and has its pitfalls. Knowledge and experience are invaluable to giving the user the best experience possible. Let’s face it, in the end, no matter our opinions, prejudices, or ego providing our clients, customers, and users with the best solution possible is what counts. Period… end of sentence…

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CodePlex Daily Summary for Monday, December 13, 2010

CodePlex Daily Summary for Monday, December 13, 2010Popular ReleasesRequest Tracker Data Access: 1.0.0.0: First releaseMicrosoft All-In-One Code Framework: All-In-One Code Framework 2010-12-13: Improved and Newly Added Examples:For an up-to-date code sample index, please refer to All-In-One Code Framework Sample Catalog. NEW Samples for ASP.NET Name Description Owner CSASPNETCMD Run batch/cmd from ASP.NET (C#) YiXiang VBASPNETCMD Run batch/cmd from ASP.NET (VB) YiXiang VBASPNETAJAXWebChat Ajax web chat application (VB) JerryWeng CSASPNETAJAXWebChat Ajax web chat application (C#) JerryWeng CSASPNETCurrentOnlineUserList Get current online u...Wii Backup Fusion: Wii Backup Fusion 0.9 Beta: - Aqua or brushed metal style for Mac OS X - Shows selection count beside ID - Game list selection mode via settings - Compare Files <-> WBFS game lists - Verify game images/DVD/WBFS - WIT command line for log (via settings) - Cancel possibility for loading games process - Progress infos while loading games - Localization for dates - UTF-8 support - Shortcuts added - View game infos in browser - Transfer infos for log - All transfer routines rewritten - Extract image from image/WBFS - Support....NETTER Code Starter Pack: v1.0.beta: '.NETTER Code Starter Pack ' contains a gallery of Visual Studio 2010 solutions leveraging latest and new technologies and frameworks based on Microsoft .NET Framework. Each Visual Studio solution included here is focused to provide a very simple starting point for cutting edge development technologies and framework, using well known Northwind database (for database driven scenarios). The current release of this project includes starter samples for the following technologies: ASP.NET Dynamic...WPF Multiple Document Interface (MDI): Beta Release v1.1: WPF.MDI is a library to imitate the traditional Windows Forms Multiple Document Interface (MDI) features in WPF. This is Beta release, means there's still work to do. Please provide feedback, so next release will be better. Features: Position dependency property MdiLayout dependency property Menu dependency property Ctrl + F4, Ctrl + Tab shortcuts should work Behavior: don’t allow negative values for MdiChild position minimized windows: remember position, tile multiple windows, ...SQL Server PowerShell Extensions: 2.3.1 Production: Release 2.3.1 implements SQLPSX as PowersShell version 2.0 modules. SQLPSX consists of 12 modules with 155 advanced functions, 2 cmdlets and 7 scripts for working with ADO.NET, SMO, Agent, RMO, SSIS, SQL script files, PBM, Performance Counters, SQLProfiler and using Powershell ISE as a SQL and Oracle query tool. In addition optional backend databases and SQL Server Reporting Services 2008 reports are provided with SQLServer and PBM modules. See readme file for details.EnhSim: EnhSim 2.2.1 ALPHA: 2.2.1 ALPHAThis release adds in the changes for 4.03a. at level 85 To use this release, you must have the Microsoft Visual C++ 2010 Redistributable Package installed. This can be downloaded from http://www.microsoft.com/downloads/en/details.aspx?FamilyID=A7B7A05E-6DE6-4D3A-A423-37BF0912DB84 To use the GUI you must have the .NET 4.0 Framework installed. This can be downloaded from http://www.microsoft.com/downloads/en/details.aspx?FamilyID=9cfb2d51-5ff4-4491-b0e5-b386f32c0992 - Updated th...NuGet (formerly NuPack): NuGet 1.0 Release Candidate: NuGet is a free, open source developer focused package management system for the .NET platform intent on simplifying the process of incorporating third party libraries into a .NET application during development. This release is a Visual Studio 2010 extension and contains the the Package Manager Console and the Add Package Dialog. This new build targets the newer feed (http://go.microsoft.com/fwlink/?LinkID=206669) and package format. See http://nupack.codeplex.com/documentation?title=Nuspe...Free Silverlight & WPF Chart Control - Visifire: Visifire Silverlight, WPF Charts v3.6.5 Released: Hi, Today we are releasing final version of Visifire, v3.6.5 with the following new feature: * New property AutoFitToPlotArea has been introduced in DataSeries. AutoFitToPlotArea will bring bubbles inside the PlotArea in order to avoid clipping of bubbles in bubble chart. You can visit Visifire documentation to know more. http://www.visifire.com/visifirechartsdocumentation.php Also this release includes few bug fixes: * Chart threw exception while adding new Axis in Chart using Vi...PHPExcel: PHPExcel 1.7.5 Production: DonationsDonate via PayPal via PayPal. If you want to, we can also add your name / company on our Donation Acknowledgements page. PEAR channelWe now also have a full PEAR channel! Here's how to use it: New installation: pear channel-discover pear.pearplex.net pear install pearplex/PHPExcel Or if you've already installed PHPExcel before: pear upgrade pearplex/PHPExcel The official page can be found at http://pearplex.net. Want to contribute?Please refer the Contribute page.??????????: All-In-One Code Framework ??? 2010-12-10: ?????All-In-One Code Framework（??） 2010?12??????！！http://i3.codeplex.com/Project/Download/FileDownload.aspx?ProjectName=1code&DownloadId=128165 ?????release?，???????ASP.NET, WinForm, Silverlight????12?Sample Code。???，??????????sample code。 ?????：http://blog.csdn.net/sjb5201/archive/2010/12/13/6072675.aspx ??，??????MSDN????????????。 http://social.msdn.microsoft.com/Forums/zh-CN/codezhchs/threads ?????????????????，??Email ????DNN Simple Article: DNNSimpleArticle Module V00.00.03: The initial release of the DNNSimpleArticle module (labelled V00.00.03) There are C# and VB versions of this module for this initial release. No promises that going forward there will be packages for both languages provided for future releases. This module provides the following functionality Create and display articles Display a paged list of articles Articles get created as DNN ContentItems Categorization provided through DNN Taxonomy SEO functionality for article display providi...UOB & ME: UOB_ME 2.5: latest versionAutoLoL: AutoLoL v1.4.3: AutoLoL now supports importing the build pages from Mobafire.com as well! Just insert the url to the build and voila. (For example: http://www.mobafire.com/league-of-legends/build/unforgivens-guide-how-to-build-a-successful-mordekaiser-24061) Stable release of AutoChat (It is still recommended to use with caution and to read the documentation) It is now possible to associate *.lolm files with AutoLoL to quickly open them The selected spells are now displayed in the masteries tab for qu...PHP Manager for IIS: PHP Manager 1.1 for IIS 7: This is a final stable release of PHP Manager 1.1 for IIS 7. This is a minor incremental release that contains all the functionality available in 53121 plus additional features listed below: Improved detection logic for existing PHP installations. Now PHP Manager detects the location to php.ini file in accordance to the PHP specifications Configuring date.timezone. PHP Manager can automatically set the date.timezone directive which is required to be set starting from PHP 5.3 Ability to ...Algorithmia: Algorithmia 1.1: Algorithmia v1.1, released on December 8th, 2010.My Web Pages Starter Kit: 1.3.1 Production Release (Security HOTFIX): Due to a critical security issue, it's strongly advised to update the My Web Pages Starter Kit to this version. Possible attackers could misuse the image upload to transmit any type of file to the website. If you already have a running version of My Web Pages Starter Kit 1.3.0, you can just replace the ftb.imagegallery.aspx file in the root directory with the one attached to this release.ASP.NET MVC Project Awesome (jQuery Ajax helpers): 1.4: A rich set of helpers (controls) that you can use to build highly responsive and interactive Ajax-enabled Web applications. These helpers include Autocomplete, AjaxDropdown, Lookup, Confirm Dialog, Popup Form, Popup and Pager new stuff: popup WhiteSpaceFilterAttribute tested on mozilla, safari, chrome, opera, ie 9b/8/7/6nopCommerce. ASP.NET open source shopping cart: nopCommerce 1.90: To see the full list of fixes and changes please visit the release notes page (http://www.nopCommerce.com/releasenotes.aspx).TweetSharp: TweetSharp v2.0.0.0 - Preview 4: Documentation for this release may be found at http://tweetsharp.codeplex.com/wikipage?title=UserGuide&referringTitle=Documentation. Note: This code is currently preview quality. Preview 4 ChangesReintroduced fluent interface support via satellite assembly Added entities support, entity segmentation, and ITweetable/ITweeter interfaces for client development Numerous fixes reported by preview users Preview 3 ChangesNumerous fixes and improvements to core engine Twitter API coverage: a...New Projects.NET Tips Repository: This project is the source code repository for all the projects, samples, and tutorials posted at vahidnasiri.blogspot.com. Its main focus is on .NET programming.a hash implement by basic array and link list: a hash implement by basic array and link listApplication Essentials for WPF, Silverlight, and Windows Phone 7: Application essentials is a simplified, small footprint redux of the Structured MVVM and Color Blending projects and is used to build WPF, Silverlight, and Windows Phone 7 applications with an MVVM architecture.Bit.ly Button: Bit.ly Button lets you use the power of Bit.ly bookmarklet to shorten any webpage (especially on sites like Facebook and Twitter). It's like a sharing button, except it will shorten the link before you share on Facebook or Twitter.Check Dependency: Check Dependency is designed to identify the dependency problems in assemblies. It is a valuable assistant to a project hat has complex dependency in many assemblies.Circo: A product oriented towards the need of having a powerful tool improving the construction process of applications. User interface for creating Entity Dictionary, generating .Net classes and also SQL model. It provides a strong productivity oriented.CoralCubeDB: This is the db for coralcube.Dotnet.Samples: Microsoft® .NET™ sample projects Created by Nano Taboada under a MIT License All projects have been coded using Microsoft(R) Visual Studio(R) 2010 mostly targeting framework version 4.0 Get a free copy of Visual C# 2010 Express at http://tinyurl.com/visualstudio2010expressElasticity: An library implementation of the Scheduler-Agent-Supervisor pattern. http://vasters.com/clemensv/2010/09/28/Cloud+Architecture+The+SchedulerAgentSupervisor+Pattern.aspxFacebook Graph Toolkit: get Graph API in ASP.NET.Grabbers: An object relational library and code generator designed to assist agile development teams generate data aware objects. InSimSniffer: InSimSniffer is a InSim packet sniffer for the racing simulator Live for Speed. It allows programmers to view and debug packets sent by the game.Irrlicht Wrapper for D: A D wrapper for the Irrlicht game engine generated by SWIG.Linq to LDAP: Linq provider built on top of System.DirectoryServices.Protocols for querying LDAP servers.ME Video Player: ME Video Player makes it easier for web developers to present medis on web pages. It's developed in C# and Silverlight by Mahyar Esteki.Mladi.com.hr: CMS system for croatian youth portalMouse Practise: A small project that creates a game to train a beginner to use mouse. Developer's Blog : http://shekhar-pro.blogspot.com Follow on Twitter : http://twitter.com/samajshekharMVVMKit: MVVMKit makes it easier to create WPF applications using the MVVM pattern.mygully-searcher: MyGully-Searcher makes it easier for Mygully-Forum-Users to search the forums for downloads. You'll no longer have to click to all forums. It's developed in VB.Net.NBooks Accounting: A simple clone to Quickbooks.Projeto Teste do curso de Pós graduação em Engenharia de Software.: Projeto teste do curso de pós graduação em Engenharia de Software. Códigos exemplos em Javascript e outros. Nayanne Araújo Bonifácio.Razor Reports - a Visualizer for the DotNetNuke Reports Module: Razor Reports is a Visualizer for the DotNetNuke Reports ModuleSiteGrabber: Groepsopdracht 2Supermarket: Hat: tTheSharePage: Project contains the core library for use in my website that i am developing for my NIIT project work. (The website will integrate facebook and twitter in a single website) The library features full custom developed facebook and twitter sdk library that can even be reused.Tip Of Day SharePoint WebPart: Tip Of Day webpartTranslit Hebrew to Russian: Application, which can translit Hebrew text into Russian.WP7 Thai Text Input: WP7 Thai text input makes it possible to enter Thai characters in WP7. It's developed in C# and were used in some of the CoreSharp's WP7 apps.

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